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Pontiac Bonneville Water Leaks

13

Comments

  • maurice142maurice142 Member Posts: 2
    I have a 2005 bonneville se, some probs:
    1. i had the ac control lights replaced 2 years ago, now the same prob. rt 2 lights are out dealer say so
    2. my trunk has water i have a sun roof
    3. my tack sometimes does pushups. seems to loose power when speeding up
    then it works ok
  • 2004bonne2004bonne Member Posts: 6
    Rocky74 & rmgoat78 - I'm new to Edmonds and have not seen the answer to this problem. I've got a 2004 Bonneville SE with a wet floor behind the driver's seat. Tell me what's wrong and what my fix is --- PLEASE! Thanks

    Jim
  • rocky74rocky74 Member Posts: 15
    I just re-read your post about cars having flood plugs under the carpet. Do you know where they're located on the Bonnevilles? That might be a good solution, to just
    pull the plug when water builds up.

    I can't figure out my car -- I vacuumed up the water from the floor in the back seat, and a couple of days later, there was MORE water in the back seat. Where could that have come from? It didn't rain in those 2 days.
  • rocky74rocky74 Member Posts: 15
    Imadizol sent me the fix. He's the expert. If you can't get in touch with him, I'll try to find his post and forward it to you. It involves taking the door panel off and re-sealing the plastic liner inside the door that keeps water from coming in. I haven't done this yet as I don't know if I want to be messing around with trying to take the door panel off myself.
  • imidazol97imidazol97 Member Posts: 27,132
    If you have a sunroof it can be the tube drain cracked off at floor level near the emergency brake. But you don't mention front floor wet. There is a rear drain along with front drains on each side. Lift rear seat cushion and look for water coming from the rear. If none, then ...

    But most likely is inner panel in the door. See my message in your carspace.com email. Click on the My Carspace in green bar at top of this page. That takes you there; or www.carspace.com/2004bonne.

    2014 Malibu 2LT, 2015 Cruze 2LT,

  • maurice142maurice142 Member Posts: 2
    hi,
    i have a 05 se, my leak is in the trunck. it comes from my sun roof, hoe's your tranny
  • njpontiaclovernjpontiaclover Member Posts: 5
    Hello there,

    I too also do have a 1999 pontiac bonneville. I have had several times of a tremendous amount of water in the trunk that was where I had first seen the water and was trying to track it down and for months was unsuccessful until I took off the tires to rotate them and looked into the rear fenderwell and to my admise I found that the entire fender well was rotted out. It was a very big piece of cancer on the body and was hidden well with the undercoating. I have to still repair the fender well and hope that will cure some of the flooding that my car seems to be getting as I have it in the trunk to the back seat and also the front seat as well as it seems to travel underneath. I also do have a sunroof as well and will have to check on the drains to see if I can find out if they are clogged. Does anyone know where all the drains are located at and where they would drain out to and end out coming out of the body at so that I can try to fish some wire up there to open it up as well as some air from air compressor?

    Thanks,
  • imidazol97imidazol97 Member Posts: 27,132
    I have read once of someone having the wheel well rust through and allow wheel splash water into the trunk. They repaired it with a piece of galvanized metal and rivets and silicon caulking.

    For the sunroof, do not use compressed air because it may pop the hoses off the connections and then you will have a leak. You might try suction from a shop vacuum to draw gunk back up and out.

    Test by using small amounts of water into each corner of the sunroof and watch to see if it comes out. For the fronts, they drain behind the front wheels. I do not know where the rear drains empty.

    2014 Malibu 2LT, 2015 Cruze 2LT,

  • syberbratsyberbrat Member Posts: 1
    I Recently purchased a 1995 Bonneville with significant headliner damage and very wet floors (all 4 floorboard areas) I suspected, before I purchased - that it had the notorious sunroof drain tube(s) problem that is mentioned in many forums. I am in the process of gutting and replacing the headliner, however I was fooling with it tonight in order to perform a temp fix on the drain tubes and found the following problems:

    The drains are made of very brittle plastic. I put this subject on the top 10 design and manufacturer blunders of all time! I have had sunroof cars for over 25 years, and I don't think I have ever experienced such inferior made products, in such an important area of an automobile. Not only do people on these forums ask where they can ‘pull the plug’ in the floorboards, but also some mention that wiring is corroding because of water damage - all of which has possibly happened in as new as 2005 models.

    So anyway, after removing all the screws and plastic clips, I partially pulled back the front passenger corner of the headliner. There was evident water damage in this area where the material had separated from the foam backing of the headliner. Carefully pulling the corner away from the pillar, I noticed the 3/8" size black-brittle-tubing (loom or flex style tubing) had separated from the drain boot on the sunroof pan. As I gently touched the tubing a 3" section broke off and fell apart in my hand. As a side note, I involve and teach my children about cars and at the time of this issue, my 16 yr. old daughter and 10 yr. old son witnessed this diagnosis - they both concluded it was unnecessarily bad drain tubing. I also removed the front passenger fender to check for blockage at the end of the drain system, for which I did find a very large mud blockage that could have been a restricting factor had the system not already been compromised in other locations. I suspect that the drivers side front fender will also have some sort of debris blockage.
    Note: you can not see this particular blockage without unbolting and spreading the fender and fender-well away from the inner structure of the car, basically removing the front fenders.

    I am an experienced fabricator with knowledge in the manufacturing and automotive industry, so fixing this problem (the right way) is not going to be a problem. Whatever advice that any of you would be kind enough to reply, will be appreciated and considered. I will also post any helpful information after the repairs have been performed.

    Before I go any further though, does any one know for sure if there are additional drain tubes in the back of the sunroof pan toward the trunk? The windshield has a crack in it and so installing a new headliner when I replace the windshield will be much easier, but I wanted to be more prepared with additional tubing if I knew there were more drains?

    I think we would all agree..... besides the mere purpose of getting from point A to point B in an automobile, we would like to stay warm in the winter, cool in the summer, and by all means, dry all year around!
  • rocky74rocky74 Member Posts: 15
    To Syberbrat:
    I am very impressed with your work on the front fenders. I'm just a middle-aged female with no particular skill regarding cars, so I am not able to do this work myself, and trying to figure out where to start to get the leaks worked out. You wouldn't happen to live near me in PA, would you? I could use some help. :-)
  • sammz111sammz111 Member Posts: 2
    I just purchased my first car last week a 2000 Pontiac Bonneville SE (no sunroof)

    Today i got new car mats and went outside to go change them as i started to take the old ones off i noticed they were damp (it rained a day before) so i put my hand directly on the floorboards, the back ones had so much water underneath them that the best way to describe it was like a tiny water bed and they were completely soaked, we then checked the front ones they were soaked as well but not like the back ones, i then opened up the trunk to find that when i opened it the water must have been in the spoiler because it leaked right into the trunk. The trunk was also completely soaked along with the whole trunk mat. We found i guess the "A/C condensation Drain plug"? i was reading other posts on this site and my dad put a screw driver in it and for a good 30 mins water was rushing out of that little thing. Then when i went out later that night the car was completely dead so im not sure if this water had something to do with it :( Also nothing else in the car was wet just the floorboards and all the seals on the doors look good but i dont know anything about cars.

    From what i can tell though something is definitely wrong with the trunk but that was the least wet part in the car so i cant really see that just from one rainfall all that water got into the car just from the trunk.

    I really am not sure what the problem is, could it have just been that the trunk had a small leak in it and the last owner never knew and that it accumulated so much over time and the a/c thing was clogged that, that is why all that water was built up there....or do i have a bigger problem on my hand where i have some monster leak somewhere

    Anything would be great just so i know where to start and if this is a problem Bonneville's have

    thanks, Sam
  • njpontiaclovernjpontiaclover Member Posts: 5
    Dear Sam,

    I just wanted to let you know that I too did a posting in here several months ago as to water issues with my 1999 Pontiac Bonnevillle SLE. I do have a sunroof though but upon review of the car and checking it out thoroughly I found a HUGE HOLE in the passenger side rear quarter panel wheel well where I would say I must have taken out about 12 gallons of water from as I had to empty my shop vac 4x and if you look under the spare tire area I had about 2 inches of water in there not to mention that the padding that was in the trunk was water logged as well. It appears that since I repaired the holes that I found in the rear wheel well that all is fine now and we have had some severe flooding here in NJ and I have been thru water that was up to the doors and since the fix of repairing the holes with a sheet of aluminum and some clear waterproof silicone sealer and lots of aluminum rivits as you dont want to use steel as to the rust, and then undercoated the aluminum with rubberized undercoating to protect even further. it appears there are no more leaks in the trunk and my floorboards are dry. I was even thinking that oh boy I will have to send out the vehicle to the sunroof shop to clear the drains out which I still will do as it has been 11 years but all is dry and I am very happy I hope that maybe you find the same problem and are able to fix it as well. I recommend taking the rear tire off and checking the undercoating very good as you will be surprised as to the amount of water that gets in from just a little hole. I hope this will help solve your leaks

    Gary
  • kts0347kts0347 Member Posts: 44
    Yes, it's a good idea to check for rust penetration as a possible source of leaks. My trunk also leaked and I lay inside while a friend ran a water hose over the deck lid. I discovered that water was coming in UNDER the truck lid weatherstripping. It is glued down at the factory, and over the years the glue had dried out. I bought the correct glue at an auto supply store, pulled off the weatherstrip and re-glued it. This cut down the flow, but I didn't use enough glue to stop it. So I siliconed all around the outer edge of the weatherstrip and it stopped leaking.
    I had another leak at the bottom side edge of my rear window. The sealer there had also dried out. A gob of silicone on a stick to reach the right spot fixed that. And, then there was a leak where the Factory had applied sealer on the metal joints at the tail lights. More silicone. And, there are several screws penetrating the sheet metal. They have sealer under the washers. All dried out. More silicone. And, finally the sunroof tubes. They exit out the rear just behind the wheel wells. They have a slip on connection right at that spot. If it comes disconnected, the water runs right into the trunk. It all heads for the spare tire well. You don't discover it until you have a serious amount of water in there.

    Also, your other problem of the battery being dead is probably because you developed a short under your floor carpets, due to all the water in there. There are a lot of wires running under there, to the power seats, as well as to the rear of the car. Many areas for a water penetration to cause a short. Sounds like the AC condensor was the culprit in your case. But, you still have the electrical problem, as well as a very smelly floor mat. I removed mine (there's a huge amount of foam rubber on the underside that just sponges up the water) in order to clean it. You can get a product at Home Depot/Lowes that will remove the mildew. Check in an earlier post in this thread for the product name. Then let it air dry before replacing. You have to pull the seats to get the carpet out. Kinda heavy job for one person, but do-able.
  • kts0347kts0347 Member Posts: 44
    They say the only things certain in life are death and taxes.
    The other thing you can be sure of with a Bonneville of that age - it will have leaks. You either fix them, or wear rubber boots. :)
  • 2004bonne2004bonne Member Posts: 6
    Sam, I too had water pooling in all 4 sections of the floor - both driver and passenger. I also had water pooling in the spare tire hold of the trunk but mysteriously, that has stopped.

    For the floor boards, I had two problem areas. I had leaks coming in through both the passenger and driver doors. Also, I had a small leak that was coming in along the windshield wiper arm (driver side) and draining in to the driver floor through the firewall.

    For the doors, water naturally drips inside the door coming in through the window cracks. It is supposed to drain out the bottom. Some of the drips splash against a plastic shield and if sealed properly, the shield deflects the water and it drains out the bottom of the door and outside the car. If the plastic shield isn't sealed properly, the water will leak into the car and get your front and back mats soaked.

    Solution is to pop off the door panel and test it for leaks. You'll need some auto body tools to help you get it off. Take your time and find some directions for removing the panel. Once you get the panel off, test it for leaks by running water from the hose against the outside of the window so that it drains inside the door. You will see how it drips. If the plastic shield is working correctly, the drips will not come through the shield. If it is not working properly, you will need to purchase some caulking at the autoparts store and re-seal it. It is the same caulking they use to seal windshields when they are replaced - very tacky and black - about 3/8" thick.

    Seal up the plastic shield and try running water again to see if the leak stopped.

    Try both doors. I didn' have a leak in the back doors.

    Good luck.
  • lotsofcarslotsofcars Member Posts: 3
    edited June 2010
    I just recently acquired a 2001 SSEi with all the issues that have been discussed on this forum including the inop windows, locks and passenger mirror. I've torn up the rear and passenger carpets and seat and found tons of water although only yesterday after a huge downpour did it show up above the carpet. How can yo even get at the rear drain tubes of the sunroof? and must you remove the headliner? It is humid and the A/C has been running heavy and I see some have blamed that drain tube. Seems like four to five different solutions, how do you know which to tackle? Everyone of them are huge jobs. Is this a job for a body shop?
    Please imidazol97, send me the info you have graciously shared. I'll try to get something fixed but I'm starting to think this car is going on the auction block soon, what a nightmare and it sounds like a very common problem in all years/models too. We have looked for any wiring, terminals, etc. that might be leading to the electrical shorts and can't find anything that would be the culprit. Is there a specific location (pic would help) that can be pinpointed for fixing the window/lock problem?
  • imidazol97imidazol97 Member Posts: 27,132
    edited June 2010
    >window/lock problem?'

    You didn't specify but I assume the driver's door works for power windows and locks, but the other three don't work. They communicate with the module in the driver's door via a brown wire that meets three other brown wires under the driver's seat, and it might be under the floor mat. I'll look for a picture if I can find a link. They are coupled with a press fitting and corrosion occurs--especially if your car hs become Noah's Ark!

    Send an email to the address you see when you click on my user name at the top of this message, so I'll have an email address for you. Your CarSpace user email doesn't seem to be working yet.

    2014 Malibu 2LT, 2015 Cruze 2LT,

  • mikelfieldmikelfield Member Posts: 4
    2001 SSEI w/ sunroof and all same the issues that have been discussed on this forum. The driver's side floor is soaked. My driver's door power lock, mirror and window works, but none of the other power windows, mirror or locks work even from their own doors. I currently have the seat removed and the carpet up on the driver's side front and rear. I will be testing with a hose for leaks, but I am more concerned about repairing the windows since the rear driver's side window is currently in the down position. I at least need to get the window up, so I don't need to cover it with a tarp every night. Can anyone specifically provide information on how to fix the wiring, or could it start working properly once it's dried out?
  • kts0347kts0347 Member Posts: 44
    Hello Cyberbrat,

    Your post dates back some, but nobody seemed to answer your question. By now you may well know the answer from DIY discovery. But here goes.
    There are four drain tubes in the Pontiac Bonneville sunroof. Two lead forward and drain down the A Pillar entering the car's front cowl sheet metal and exit in the gap between the cowl and fender inner. The drain ends are invisible without removing the fender, as you say.
    Two others lead rearward and drain down the C Pillar and lead off into the trunk and exit into the trailing edge of the fender well. The drain ends again are invisible under the car.
    The drain tubes push fit onto the large plastic tray that catches the rainwater coming through the sunroof opening. Pontiac's engineering intent was not to attempt to seal the sunroof against the roof sheet metal. Instead, they allowed for a gap, and then caught the moisture in a plastic catch pan under the window (and above the headliner) with four drain outlets - one on each corner of the pan. The first leakage problem is that the drain tubes sometimes separate from the plastic tray outlet. You have to drop the headliner to verify this. The second leakage problem is that the drain tubes are made in several sections press fitting together. These sections can separate (and do, if you attempt to clear the tubes using compressed air). The sites where the sections come together are in extremely awkward locations, and require cutting of insulation etc. to find. The third leakage problem is the tubes tend to clog up with debris. When that occurs the catch basin in the roof simply overflows, and gravity takes it to the floor via the roof pillars and then following the hard trim. I have cleaned my tubes two years ago, and they are clogged again.

    If anyone has a simple method of cleaning the tubes without blowing them apart with an air hose, please add it now.

    That said, the sunroof isn't the only source of leaks in a Bonneville. The doors themselves are sources of leaks. The door design uses a sheet of polyethylene adhered to the door inner sheet metal to keep moisture out. Over time, the mastic used to adhere the sheet simply releases, and water flows into the car through the doors. The solution is to remove the door inners, and re-adhere the polyethylene sheet with new mastic or a high quality sealant.

    Then there is the air conditioner drain tube. It also plugs up. When it does, all the air conditioning condensate has to go somewhere, so it flows right onto your carpet. Fortunately, the AC drain hose can be seen under the car, and a coat hanger will unclog it.

    And, owners also report sundry leaks from windows and cowl sheet metal joints that had factory waterproofing applied to seal them. This are tedious to locate but fortunately are not too common. Sunroof, Doors and AC are the usual culprits.
    :D
  • rocky74rocky74 Member Posts: 15
    I am no mechanic by any stretch of the imagination, but you or your mechanic should take a look at the wires to see what they look like. What I was told by the mechanic at the dealer's was that the wires were corroded and they had to remove the corroded parts and replace it with new wire. Once that was done, I could open all four windows (one rear window had been broken for a while), and I stopped getting most of my idiot lights turned on, although the security light tends to stay on again.

    We had horrible rains today, and a few days ago, and mysteriously there was no leakage into my car. The only thing I did differently was move some stuff around in the trunk, so I'm thinking that the water in my car leaked in through the trunk somehow.
  • njpontiaclovernjpontiaclover Member Posts: 5
    I have a 1999 Pontiac Bonneville SLE I have replaced this past year due to problems with charging system a rebuilt GM Alternator, and a brand new 72 Month Delco battery and the charging rate was fine it has dropped some but not enough not to worry.

    I did last summer do a complete renovation to my AC system as I did have a leak where it would not stay charged so I did go ahead and get a new Aftermarket AC Clutch and compressor, a new GM AC Condenser, New AC Lines, and a new AC Acumulator tank and recharged the system and it has stayed charged and is sitill very cold. I did not have problems with the charging system last summer after replacing the entire AC.

    However now that the warmer weather is here and I have been using the AC more often there is a drop in the voltage meter that is at about either 11.5 or 12 volt line and it does go back up to about maybe 13 when accelerating or raising the idle with foot on the gas but when you take away the RPMs it drops?

    Does anyone know what may be causing this drop? Could it be a bad switch on the AC?

    I have also got this lousy squeal that sounds like a bad bearing some where in the front of the engine? I have replaced the AC compressor and clutch and also replaced the alternator my only other items that still would need to be replaced to try to figure out where and what the squealing is are the Belt tensioner, the Power steering pump?

    Thanks,
    Gary
  • njpontiaclovernjpontiaclover Member Posts: 5
    It took me forever to try to find the leak from my 1999 Bonneville SLE which does have a power moon roof, and the leak was in the trunk the entire time and it leaked so bad that it had soaked thru all 4 sections on the rugs and the passenger side and rear passenger side were the worst of them. It appeared that the entire rear wheelwell on the passenger side was rotted out and thru as you could see clear as day and I did repair the holes and sealed it up good and wha la complete satisfaction and no leaks and dry floors after torrential rains and driving thru several flooded roads this spring.

    My way of fixing the repair was to get a piece of aluminum and shape it to the way the wheel well is and then I fastened it up with aluminum rivits to the existing wheel well and sealed the aluminum to the existing wheel well, and also sealed up all the rivits and the seams as well, and then undercoated the entire patch and have not had any leaks at all as well as the trunk staying dry and the entire floors in the vehicle.
  • pontiachepontiache Member Posts: 6
    2002 SLE Black...Still a looker. This weekend the drain tube will be fixed and door panels re-sealed. The carpeting has been out since November. I cleaned that immediately. (large recycle bin) (clean) 2 cups of bleach and and laundry detergent 80 gallons of water and a large stirring stick (broom). I been driving around with just the drivers seat in the car since November and no carpeting. Almost a Nascar feel. The last thing I'm going to do is drill some drain holes (just in case) and clean the wire connectors under the drivers seat. At best I'll be able to trade it in without the bad smell in the car. Hope all the windows work after cleaning the connectors. Anyone with last minute suggestions would be appreciated. Wish me luck. Pontiache
  • mikelfieldmikelfield Member Posts: 4
    Below is everything that I did and now have no problems. I don't think it's necessary to drill holes. I just finished fixing my powers windows, locks and leak this past weekend. I removed all of the electrical tape,and plastic covers to expose all of the wires running from the front to the back and across (under the seat)and looked for any disconnected wires. I finally found 2 beige/tan wires that were separated from each other. Apparently, the water made the wires brittle and the separated, so I spliced the wires and used a connector, the windows and locks were repaired. I poured water on the door and in the sunroof drain holes. I found the door and sunroof were both leaking. I resealed that plastic to the door with glue and had no more leak there. Here is a link to an easy sunroof leak fix that I used which took not much time at all and worked great. http://www.gmforum.com/showthread.php?t=247853 good luck.
  • pontiachepontiache Member Posts: 6
    Mike, I'm following the advice of an earlier thread. The rubber hose did disconnect from the plastic tube. For that I will use silicone and 2 small hose clamps. I was thinking of using clear silicone for the door shields. If you have suggestions on using something else it would be much appreciated. After I pull the drivers seat back out I will do the wires and connectors. Last but not least I will get mama to give it the garden hose test while I'm in the car and proceed to the car wash for one last inspection. This has been very disheartning. I understand now why there is no more Pontiac division. Next project is the Transmission which hard shifts between 2nd and 3rd. Mine was made on Friday and hour after they made the announcment that they were going under. I'm sure of it. Cheers
  • mikelfieldmikelfield Member Posts: 4
    I'm not sure what type of glue I used, but I believe it was called gorilla epoxy.good luck
  • imidazol97imidazol97 Member Posts: 27,132
    >I was thinking of using clear silicone for the door shields

    There's an extra sticky, gooey black adhesive for automotive use that someone recommended for sealing along the bottom of those plastic shields where the bottom "V's" directed the water to the openings in the metal to drain down.

    I recall the term butyl caulking also was used in the past. I'd check at a full service parts supply store for something that will remain tacky.

    2014 Malibu 2LT, 2015 Cruze 2LT,

  • pontiachepontiache Member Posts: 6
    Thanks for the suggestions. Pontiache
  • 2004bonne2004bonne Member Posts: 6
    Mikelfield, I had the same problem - actually two problems. My doors leaked into the cabin (problem 1) and the flooding on the floor shorted out the wiring under the driver's seat which controlled the power to the doors. To fix the problem of the doors (its easy) you must remove the door panel. There is a 24" x 30"W thin plastic sheild that keeps water from entering the cabin. It is leaking and needs to be resealed. I forget the name of the black caulking you need but it is the same stuff they use to seal new windshields. Replace the caulking between the plastic shield and door and replace the door panel.
    to find the bad wires, I had to take this to the dealer to repair. it was under the drivers seat and they had shorted out. Good luck.
  • hdrider1993hdrider1993 Member Posts: 2
    I have a 2002 bonneville sle with sun roof. I have water leaking in under all four rugs. Does anyone have pictures of how to get door panels off and pics of how to fix the sun roof tube leak. I have read alot of the links on here and it has been very helpfull. I thank all of you for your help and for a great site.
  • 2004bonne2004bonne Member Posts: 6
    The water leaks down the window and into the door. There is a piece of hard plastic that deflects water through the exit holes at the bottom of the door. If it isn't sealed correctly, the water leaks through the panel into the floor and causes a lot of mess - electrical shorts and mold. Buy some body panel tools at the auto parts store (cheap) and pop off the door panel. It's a little tricky but take your time and you won't break anything. Tricky part is getting the panel back on correctly.

    Remove the plastic barrier, clean the old sealant off and replace the sealant with new. Its the same stuff they use on windsheild installations.
  • hdrider1993hdrider1993 Member Posts: 2
    Thanks for the info and when i got all the panels off all the plasic on all doors was not stuck. I redid all doors and now we wait for rain to see if leaks are stopped. Thanks again
  • rickster52rickster52 Member Posts: 2
    I am having issues and would like to see the photos you have on how to resolve the problem of water leaking in all four corners of the roof of the car. It has a sunroof and I have tried to run plastic line down them and can not find out where it it going. The two front drain holes are easy to find. It is the rear ones that puzzle me.
    Do I have to remove the head liner to get to the sunroof drains in the back?
  • mikelfieldmikelfield Member Posts: 4
    Open the truck and just remove the carpet on the sides on the truck and you'll see the tubes. The tube that goes to the rubber plug to the wheel well will be disconnected from the tube that comes down from the sunroof.
  • kts0347kts0347 Member Posts: 44
    Here is a little info
    There are four drain tubes in the Pontiac Bonneville sunroof. Two lead forward and drain down the A Pillar entering the car's front cowl sheet metal and exit in the gap between the cowl and fender inner. The drain ends are invisible without removing the fender inner.
    Two others lead rearward and drain down the C Pillar and lead off into the trunk and exit through the sheet metal just behind the wheel wells on both sides of the car. Remove the side carpets in the trunk and they will be clearly visible. Black 3/8" tubing leads to a 1" rubber grommet passing through the sheet metal right down where the fender inner meets the trunk floorpan. Pull the grommets out of the sheet metal and cut off the little lips you will see on the outside surface. They get stiff or stuck together and tend to block water from draining. It just backs up and overflows the drain pan in the roof. Or possibly the tubes will be disconnected at the elbow molded into the inside edge of the grommet. If you have water in your trunk, they are disconnected near the grommet. If you have water in your passenger compartment they are backing up and overflowing the drain pan.
    The drain tubes push fit onto a plastic drip tray that catches the rainwater coming through the sunroof opening. Pontiac's intent was not to seal the sunroof against the roof sheet metal. Instead, they allowed for a gap, and then caught the moisture in a plastic catch pan with four drain outlets - one on each corner of the pan. The first leakage problem is that the drain tubes sometimes separate from the plastic tray outlet. You have to drop the headliner to verify this. The second leakage problem is that the drain tubes in both front and rear are made in sections and they can separate. The third problem is the sticky lips on the rear grommet. The fourth problem is plugged outlet holes behind the fender inners on the front drains. There may be a fifth problem, of debris blocking the tubes themselves, but so far I have not found that on my car.
    Hope this is helpful.
  • kts0347kts0347 Member Posts: 44
    Here is a little more info. Another good site to visit is http://www.pontiacbonnevilleclub.com
    for information about Pontiac Bonnevilles. The owners there are very knowledgable.

    Here is a specific forum on that site, where water leak issues are discussed and several great photos are posted.
    http://www.pontiacbonnevilleclub.com/forum/viewtopic.php?f=14&t=10661

    Here are more links dealing with known leak problems causing wet floors

    sunroof drain line connections become disconnected
    http://www.pontiacbonnevilleclub.com/fo ... =43&t=1688

    Door rain shield seal repair
    http://www.pontiacbonnevilleclub.com/fo ... 43&t=11470

    :)
  • pontiachepontiache Member Posts: 6
    Took care of my water leak problems 2002 Bonneville, carpeting and interior back in. Driver window works, but not the other three windows. They don't work from the individual switches or the drivers console. I have a gas gauge the is irradic, but other gauges seem to be OK. Before I put the carpet and seats back in I checked the connectors and grounds and seemed fine. Anyone have similar issues ? Any and all suggestions welcome.
  • destiny5destiny5 Member Posts: 2
    Like everyone else I am getting water on the floor behind the drivers seat and underneath it. Have spent money fixing the wiring because of this. I am now also getting water in my trunk where the spare tire sits. Can anyone help me?
  • imidazol97imidazol97 Member Posts: 27,132
    edited February 2011
    Look for the corroded connector where the tan or brown wires are connected under the driver's seat rear area. This is the communication to the other three doors for windows.

    This shows it. It is not my picture. It where the red connector binds all four wires in a connector that corrodes.
    image

    2014 Malibu 2LT, 2015 Cruze 2LT,

  • imidazol97imidazol97 Member Posts: 27,132
    I've read where people have a hole in the wheel housing due to corrosion. The spinning tire pushed water into the trunk. I've read about leaks with the air dam on the trunk. I've also read about leaks around taillight housings.

    2014 Malibu 2LT, 2015 Cruze 2LT,

  • rickster52rickster52 Member Posts: 2
    I believe that the water leaks came from the sun roof. I replaced the front two with clear tubing that fit inside the existing corrugated tube very well. The two rear tubes were solid but clogged. The flexible plastic grass cutting line worked well until there was a clog that was stuck. Some compressed air in a can did the trick there. All seems well now.
  • 2004bonne2004bonne Member Posts: 6
    You've got to find where the water is getting into the car's cabin. I had it coming in at two places -- just behind the parking brake pedal on the firewall and through the driver's door. Put a water hose on the roof of the car and the driver side door and sit inside. I took out the carpet and the driver's seat so I could find the leak. It's not hard to take out the seat but the center console is a bit difficult. Be patient and take your time. Don't force things or you'll break them.

    If you've got the firewall problem, that's easy. I put some silicone sealant in the hole and it stopped.

    If there is a leak coming into the cabin through the door (you'll usually see it coming in between the door panel and door frame, you've got to pop off the door panel. Use some plastic tools from Harbor Freight (cheap) and pop off the door panel - take it slow and easy and don't break the clips that hold it in place.

    Inside the door is a plastic shield that is supposed to keep the rain water from leaking into the car and directs it down to the drain holes at the bottom of the door frame. What happened to me is the SEAL that keeps the plastic shield tight agains the door frame fails. The plastic shield needs to be removed and resealed. The sealant is the stuff you put on your replacement windshield. You can get it at the auto parts store. It comes in a box and is a long string/bead of sealant. Remove the old sealant on the plastic shield and put the new stuff on. It's real sticky and adheres beautifully to the metal door frame.

    Reinstall the shield, put the door panel back on and let it cure for a day. Try the water on the door again and see if it leaks before you put the carpet back in.

    You might try your other doors for leaks too. Three of mine leaked.

    Good luck.

    Jim
  • mikewelch12mikewelch12 Member Posts: 1
    i pretty much have all the problems people have been having on this forum. i need that email with help...any help will do, i have water everywhere. All drain tubes are clogged and wont blow out. Im thinking about putting new tubes in. welchartgalleria@gmail.com is my email
  • kts0347kts0347 Member Posts: 44
    edited February 2012
    I had an 02 Bonneville that had almost all the leaks. Here is the most likely culprits:

    1) Sunroof Drain Tubes: There are four drain tubes running down the four corners of the cabin. They block up and then water overflows the drip pan under the sunroof and flows down the pillars to the floor. DON'T Attempt to blow them out with an air hose. They consist of several sections friction fitted together and the air pressure will just cause the sections to separate and then it's a big problem, requiring a whole lot of trim to be removed to join them back together again. The source of the blockage appears to be small molded nipples at the very ends of the tubes. These nipples are like lips that are designed to be normally shut to prevent insects from creeping up the tubes. They are supposed to open with water pressure buildup. But like all things rubber, after several years, they become either brittle or sticky and then they don't open anymore. The solution I applied was to simply trim them with a scissors. Sounds easy right? Not so, they are in very awkward positions. To access the two front lips, remove the plastic inner fender by pulling out three plastic pins. Remove the inner fender briefly and you will see a black rubber fitting on the rear side of the fender, exiting out of the firewall/cockpit sheet metal. You can trim the lips from under the fender. Water might even rush out as you are trimming. The rear drains are accessed from the trunk, by removing the side inner trunk liners. You will see a tube coming down over the rear fender wells, and terminating in a large black plug right behind and at the bottom of the fender wells. Pull the plug towards you into the trunk, and on the exterior side you will find the offending lips. Trim them off, replace the plug and you are in business. The sun roof leak should be fixed, unless you have disconnected the tubes somehow during your tweeking. If you still have problems, you will have to drop the headliner and pillar trims to inspect for separation problems.

    2) Door Trim Leaks: Water flowing down the window channel will actually flow into the passenger compartment instead of through openings at the bottom of the door, due to the slope of the door. To prevent this, Pontiac sticks a plastic sheet over the door inner to trap the water inside the door and force it to exit out the openings. Over years, the mastic sticking the plastic sheet to the door inner metal releases, and water flows freely into the cabin. Remove the door trim panel, and apply fresh sealant to the plastic sheet to cause it to adhere to the metal. Don't use epoxy, the sheet may have to be removed in future. Use mastic, and perhaps some gasket sealant.

    3) Backed up condensate tube from the AC: Just like the sunroof drains, the air conditioner has a tube that vents condensate water just in front of the firewall. It also has lips that seal and they can get blocked, which causes the condensate to back up and flow into the passenger compartment. This can usually be cleared from the underside when the car is on a hoist.

    Be sure to clear up your leaks. Beyond being annoying, there is a lot of electrical stuff under the floor mats, and when it gets wet and rusts, you start to experience a host of electrical problems like windows not working, seats not adjusting, etc.

    Hope this helps. There are great tutorial videos on this site and on a related site www.PontiacBonnevilleClub.com that can help you with details and photos of the process for removing door trim, etc.

    Updated to correct the URL for Pontiac Bonneville Club.
  • bentstorkbentstork Member Posts: 1
    I have a 2002 Bonneville SLE, I have owned the car since 2009 and started developing water leaks summer of 2012. The right side of the interior would get wet, both front and rear carpeted areas. The rear especially as that is the lowerst point. I vacummed most of a gallon of water out of the carpet twice that summer. As others have done on this forum I took the time and removed the seats and console and stripped the the soaked carpetting out and let them air dry. I did the wet tests, running a hose on the outside. I discovered 3 leak sources and fixed two of them. The plastic shield on the front right door was the main culprit. Everything seemed fine and good over winter and even in this spring until recently. But again wet floors. So again I stripped everything out and started over. The leak now is coming from under the firewall in the extreme right corner. I have no idea where from and really don't wish to strip the dash down. Does anyone have any idea where it is probably running in and if there is a easy fix? Thanks
  • kts0347kts0347 Member Posts: 44
    Ben,

    I had a 2003 Bonneville and had ALL the classic water leaks. Glad that you have conquered the leaking door seals. They will all become loose in time and a good sealant is needed to cause them to retain a relatively permanent bond. I initially tried household sealants and they survived only a matter of months before re-releasing. Save your energy on a repeat repair and get a good automotive bonding product such as I describe below, from an auto supply store.

    You didn't mention whether you have a sunroof, but the source of the current leak points to sunroof. There are four vent tubes that drain water that enters the roof around the perimeter of the sunroof. It's not designed to keep water out. Rather its designed to drain the water off. There is a drain pan surrounding the sunroof, and there are four drain tubes. When the tubes block, the pan overflows onto the headliner, and flows down inside the trim pieces until reaching the floor. The front of the roof is the lowest point hence the water drains off the headliner into the windshield A pillar trim, then down the side kick panel trim eventually finding the carpet.

    Two tubes route down the front windshield pillar, out through the sheet metal on the side kick panel under the IP, and ultimately dump to the open air behind the plastic inner fender panel.

    The other two route down the rear window pillar, into the trunk and then dump to the open air behind the wheel well.

    I initially thought that the tubes were plugging with debris and mud, and I tried dropping the head liner and blowing them with compressed air to clear them. Bad idea. They aren't a single run of tubing, instead they consist of a series of tubes that are interconnected one inside the other (pressure fit). Blowing with compressed air simply causes these connections to separate, and then you have a real problem getting them reassembled and have to remove a lot of trim to access them.

    However after much work, I finally found that the real blockage wasn't inside the tubes, it was at the very end, exiting out of the car. The engineers designed the tubes to pinch shut to prevent small insects from entering the vehicle. The weight of the water accumulating in the tubes is supposed to provide sufficient pressure to open the pinched ends and it works - when the hoses are new. After several years these pinched ends become a bit sticky, and simply don't open and thus the water overflows. I solved my sunroof leak problem permanently by simply clipping off the pinches with a wire cutter. The rear ones are relatively easy to locate. Just pull off the trunk side trim and you will observe the hoses snaking down and over the wheel well and finally making a tight turn to exit the sheet metal. There is a grommet on the end of the tube where it exits through the sheet metal that you can pull out to reveal the pinch point that you want to snip. Just push the grommet back in the hole and the job is done. In order to remove the side trim, no tools are needed. The hard plastic piece crossing the back of the trunk has to be removed by hand unscrewing some black plastic knobs. There are some similar black plastic knobs securing the side trim.

    The front tubes are a little harder to access. The plastic inner fender has to be removed. This can be done with the wheel in place with a little practice. Pull out the plastic push clips around the fender opening perimeter and the inner fender will be loose. Then just try to get the rear part of it free so you can access the hose exit point. You can snip the pinch point off with the hose in place in the sheet metal.

    Then test the whole system with a hose and ensure that you get water flow on all four corners. Just look for puddles on the ground since you won't be able to see the actual hose ends.

    PS: There is the same pinch system on the end of the hose that drains condensation out of the air conditioner. This can also stick and cause condensation water to overflow the HVAC and leak into the passenger compartment.

    Another source of water leaks that I encountered was in my trunk. My spare tire well would fill with water. I discovered that water would leak at the rubber weatherstrip. Not over the top - instead under it, where it was stuck on a sheet metal lip. The solution was to pull it off, and reseal the weatherstrip to the lip with a good dollop of glue all the way around. I used Pro Seal brand black RTV silicone Instant Gasket, that I purchased at the auto supply store.

    I also had two other sources of trunk leaks. The tail light attaching studs that pass through the sheet metal are secured with nuts backed with a mastic. Eventually they started to leak. The Instant Gasket worked here too. The final source of trunk leaks was the rear window itself. The mastic used to secure the window eventually developed leaks on the lower edge due to the design that accumulates water. A coating of sealer from the inside of the trunk provided a clean finish outside and solved the leaking problem.

    Best of luck. I operated my car in the heat and rain of Florida, it was black color and I kept it outside 24/7 for its entire life so it endured the ultimate of endurance tests. Ultimately all the factory seals failed but fortunately they were detectable and easily repaired - - if I only knew where to look and what to do. The discovery part was the big time consumer. Hope this write up helps you to shortcut the repair time.
  • cohlmcohlm Member Posts: 1
    I also have a 2000 Bonneville LE with water accumulating in the rear driver's side floor board. I have noticed prior to this that my trunk would have a slight amount of water droplets, but I thought it was dripping from my trunk lid when I opened it. I had a previous 1987 Bonneville SE that did the same thing and supposedly it was coming from a trunk leak. I was able to afford to have a mechanic fix it at that time, but I am now not able to afford having it repaired. I could use any help that you could offer for me to help get this problem solved. I do have a sun roof as well, Could the leak be coming from there since I have noticed the trunk being affected as well?
  • bonneville3bonneville3 Member Posts: 2
    Hi, I also am having a water leak in my 03 Bonneville. Could you please send information to me on what to do. I do not have a sunroof.
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    You might want to scroll through previous posts here. There's a lot of good info on what to look for.
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