Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Did you get a great deal? Let us know in the Values & Prices Paid section!
Meet your fellow owners in our Owners Clubs

Pontiac Bonneville General Maintenance and Repair



  • imidazol97imidazol97 Crossroads of America I70 & I75 Posts: 23,199
    You may have a system comparable to my LeSabre. I had a slow movement of the various vacuum motors that pull the vanes inside the box that directs all the air under the dash.
    If you hear a vacuum leak under the right side, that could be the reason there not much happening. The vacuum line comes in at the right side from the passenger compartment. Then it goes to a switching device that's electrically controlled on the automatic air system. From there hoses come out to 5 or 6 vacuum motors that pull the vanes. Any of those vacuum lines could be damaged.
    You have to take off 3 or 4 little screws under the dash above the passenger's feet to get up under there. Then you need to take off four or 5 screws that hold the glovebox up. You need to be able to see through that opening to see the vacuum lines coming in.
    I have a service manual so it's not as intimidating as it sounds to me.

    I moved around the vacuum lines and tried to disconnect the main one. The system started working better, so one of those lines wasn't connected well or something. The dealer had been into that area with a fan motor controller problem a couple years ago and the air never seemed to blow out as well after that.

    IF you have no vacuum to the controller box under there, the air should be coming out the defrost vents. That's what the system does when there's no vacuum to control it. Try feeling up there to see if you're getting air when you first start the car. Then see if it tries to move the air to other output after a minute or more of running the motor.

    2015 Cruze 2LT, 2014 Malibu 2LT, 2008 Cobalt 2LT

  • henrylhenryl Posts: 15
    Thanks for all the advice It was tracked down to the main computer since it was the diaphram was tore and the lines were brittle. All the vaccum line from the a/c go to there. That is why it wasnt blowing hard till I got on the freeway. At idle speed the vaccum was low. Next problem a/c not cold. When the system was evacuated. The revious tech, put 1-1 1/2 oz of pag oil anf way too much freon. The gauges said 300psi high side and 36psi low side. Got that fixed now colder, but im still debating if i should replace the computer and the lines because its still going to be 900-1000 dollars. Its been to 4 a/c shops and every one told me something diffrent. The other shops told me what it was and when i could drop it off. This guy actually walked me through it and showed me the problem and explained it. Man it sure is hard to find a good tech. Also didnt charge to look at it. Thanks Guys
  • I have a 2001 Bonneville that has developed paint bubbling along the front edge of the hood. I am told this is aluminum corrosion and it is covered under a GM bulletin ID#1230005 and is referred to as premature aluminum hood corrosion/blistering. This document lists all makes & models of GM vehicles experiancing the same problem. It also appears on Buicks, Chevs, Olds. I experienced the problem at about 75000 miles and,like a darn fool, didn't complain about it until 92000 miles. I was told that I should call 1.800.GMcares and I soon found out GM does not care. I maintained it was the same as rust thru and should be covered for 6 yrs. or 100K miles. They say 36000 miles is all they will cover. I have since found out that in Wisconsin they are covering it to 100K but I live in Michigan and no such luck here. Anyone else experience this prob?
  • I have a '93 Bonneville SE with 137K miles on it.
    Lately the car surges while maintaining a constant speed or under slight acceleration anywhere from 40 to 80 mph. It seems as though the transmission can't decide which gear to be in.
    I also notice a clunking metal sound while the car is in neutral or park and the revs are above 1200 RPM (such as after a cold start). I can also demonstrate the clunk if I increase the revs from idle while in neutral or park. I have seen some other posts related to these problems and am wondering if there is anything a non-mechanic can do?
    Thanks for any help.
  • This is my first post here so please bare with me. My wifes 98 bonneville's security light stays on and won't go off. Now at low speeds the cars chime goes off and the engine dies. You have to come to a complete stop and put the car in park to restart the engine. Somebody told me the chip in my key was bad. I have the same problem with 2 keys. Anybody have any suggestions?
  • imidazol97imidazol97 Crossroads of America I70 & I75 Posts: 23,199
    Had mine come on in a 93 LeSabre. The wiring to the ignition where the key chip is sensed starts to break. It's multiple small wires and as they break, the resistance of the wire changes.

    The security light comes on. If the wire breaks completely, then the car won't start because the chip can not be sensed at all.

    I was hoping in 98 that flexing and breaking problem had been fixed. But the car shouldn't die from that once it's running, as I understand the setup.

    2015 Cruze 2LT, 2014 Malibu 2LT, 2008 Cobalt 2LT

  • I also have a 2002 ssei that also has major issues with water leaks. All started with windshield to trunk now to water in floorboards. Dealership has had my car 24 times due to leaking and other issues.
    Finally got windshield & trunk fixed but not the floor. I was looking for someone who had or has the same problems as I have had with their car. Mine comes up under the car when you are driving in the rain.
  • idntnvuidntnvu Pulaski, VirginiaPosts: 254
    Wow, finally, after all this time someone else with a '93 signs on!
    My sister's (formerly my mom's) '93 SSEi has never had that sort of problem, but, I do know for a fact that there were many transmission failures in the '92-'94 Bonnevilles. A friend of mine had an SSE and had the transmission replaced somewhere around 150k miles. My sister's has 117k on it.
    As for the clunking, this car used to pop and "backfire" sometimes when you reved it up to a certain rpm, but I think it had something to do with a limiter to keep it from over-reving.

    As for leaks, I think thats been a problem with Bonnevilles dating back to the '92 generation. the '93 we had leaked quite a bit, and my dad took some silicone and filled in around all the doors, but water would still come in, presumably from the sunroof. I had a problem with a '98 Suzuki of water coming up through the floor, and it turned out it was a plastic cap that was supposed to be filling a hole in the floorboard had come out and was allowing water to come in. Especially a pain when you go through a car wash.
  • I have the same problem which I posted in past I think it was somewhere between post 1250-1300. I still have the shuttering at highway speeds I've been told its the Torque converter clutch and solinoid valve which comes down to I need to get transmission rebuilt.One thing that has helped was Lucas transmission treatment fluid.
  • I have a 1996 pontiac bonneville Se with 178303 miles. I been losing coolant about a half gallon every 4 days unknown if head gasket leak or dripping it out. The only drips i've seen is on the bottom of the back firewall where A/C condensation comes out but seems like a lot more then normal and not the red dexcool color.I cleaned the engine with Gunk engine cleaner and water hose the next day I had my check engine light come on which I was told was a code for Misfire cyclinder#6 and a loud ticking(like fuel injector but very loud). My mechanic thinks its a collapse lifter. As the engine was running the ticking stopped but engine light still on.I changed the #6 coil pack and engine light went off.Help any Ideas will be appreaciated,thanks.
  • alcanalcan Posts: 2,550
    Pull the plugs and inspect for signs of coolant contamination. The upper intake plenum is probably warped in the EGR tube area, allowing coolant to enter the intake.
  • imidazol97imidazol97 Crossroads of America I70 & I75 Posts: 23,199
    What are the signs on plugs of coolant (Dexcool) contamination? What should I look for when I change my own plugs?

    2015 Cruze 2LT, 2014 Malibu 2LT, 2008 Cobalt 2LT

  • alcanalcan Posts: 2,550
    White deposits on the spark plug electrodes, electrodes wet or very clean looking. Also, crank the engine over with the plugs out and look for any coolant or vapour coming out of the plug holes. We do that with a cooling system pressure tester installed, which will force coolant past leaks and into the cylinders.
  • bkm645bkm645 Posts: 1
    I have a 96 bonneville with 93k miles on it. And I drove to the mall in it but, when I came out to go home it would not start. The radio worked, but when I turned the key it did nothing. So I went to sears in the mall and bought a battery. Installed it, both of the screws were nice and tight, but it still would not start, it did the exact same thing. And help would be greatly appreciated.

    Brian Mullins
  • jwallyjwally Posts: 71
    Regarding post#1347-1350 I like to know if pulling plug and inspect for signs of coolant contamination. How will i know if i need intake plenum and/or head gasket? How can i determine if i need either one or both? when i turn key it cranks but takes a few seconds to run. I use a full gallon on one way 45 mile trip. No signs of leaks. when car idles it leaves one foot round wet spot but no white smoke. also when stop at light feels like it wants to stall and sputters. check engine light on steady and sometimes blinks, also traction off light goes on and off at times. Please alcan or anybody any help is appreciated,thanks. oil pressure at idle about 40-50.
  • alcanalcan Posts: 2,550
    If the coolant level is dropping in the overflow tank but there are no external leaks, it has to be going somewhere and that somewhere is usually through a warped upper intake plenum. I've already posted how to check for this condition. Head gasket failures with 3800's are rare.

    1 full gallon of fuel for 45 miles = 45 m.p.g., very impressive gas mileage.

    The wet area is probably air conditioning condensate, normal.

    For the hard start, locate and remove the vacuum hose attached to the fuel pressure regulator. If there's any evidence of gas in the hose, replace the regulator.

    If the check engine light is on have it scanned at any AutoZone (no charge) and post back with the stored trouble codes.
  • imidazol97imidazol97 Crossroads of America I70 & I75 Posts: 23,199
    Did the dash warning lights stay on after you put the key in -- specifically did the 'security' light stay one. That means the key resistor wasn't being read right. It stays on for three minutes if you try turning the key 3 times and the resistor is wrong. After 3 minutes with a working resistor you can start the car.

    Do you have a second key? Try it -- if the security light on the dash is staying on. I had a problem a few times with dirt, lint, goop, on the resistor contacts not letting the reading be correct. Cleaning with pencil eraser works. But I had to try my second key.

    I also had the wire to the lock cylinder start breaking strands from flexing the tilt wheel up and down. That caused the light to go on but the car still started. If the wire breaks too many strands the resistor reading to far off and the car won't start because it thinks it's being stolen.

    2015 Cruze 2LT, 2014 Malibu 2LT, 2008 Cobalt 2LT

  • jwallyjwally Posts: 71
    1 gallon of antifreeze/water not fuel. the one foot round water spot is from the exhaust pipe(tail pipe). sorry i wasn't clear before. hope this helps you help me with more ideas. thanks Alcan(your an asset to the forum) and all.
  • alcanalcan Posts: 2,550
    First, pick up a block and head check kit from any parts store. It checks for the presence of hydrocarbons (fuel) in the radiator. If so, a head gasket is blown or a head's cracked. Neither is likely.

    Next, remove the spark plugs and inspect them as mentioned previously, install a cooling system pressure tester on the radiator and leave it pumped up for a few minutes, unplug the wiring harness from the ignition module, crank the engine over, look for any coolant mist coming out of the plug holes. Probably #4 and #6, rear bank driver's side. Would probably also account for the check engine light, usually code P0300, random multiple engine misfire.

    The throttle body, which attaches to the upper intake plenum, has coolant passages around it to promote cold weather driveability and throttle response. The coolant passages are between the lower intake manifold and upper plenum. The EGR (exhaust gas recirculation) tube is also right there, and heat from the exhaust gases degrades and warps the plenum over time. A slight gap develops between the manifold and plenum, coolant starts leaking into the manifold, and you now have an engine which consumes coolant.

    Keep driving it like that and you'll discover either A: coolant doesn't compress in cylinders and you have a bent connecting rod or wiped out rod bearing, or B: none of the engine bearings like being lubricated with coolant. Either way, you'll be looking for a replacement engine or scrapping the car if you don't get it corrected.
  • I have the exact same problem in my 95 Bonneville- both with the security light and the alarm going off unexpectedly. Any information that would solve this problem would make me and my neighbors very happy.
  • hey, I was in a wreck 12 months ago and my weather stripping around the window and driver and passenger doors woun't hold a seal. do ya have any advice???
  • If your weather stripping is new or in good shape theres not much you can do there..If it is mushed, cracked of extremely flimsy then replacing might solve the problem. If the door is slightly out of alignment then you will have to adjust it at the hinges. Open and close the door a few times very slowly and listen for a perfect click.. If its hitting hi or low you will be able to tell.. Good Luck with it
  • I have 1997 bonneville with climate control. The blower motor is going on & off even though the display shows high. Does anyone have any ideas.
  • imidazol97imidazol97 Crossroads of America I70 & I75 Posts: 23,199
    Had problem with blower motor changing speed and not going on higher speeds. It was a control panel for the speed adjustment... don't know the name. B ut it was an expensive repair for a 'switch.'

    It had a power transistor on it and some small items. Maybe about 4 inches by 2.5 inches.

    2015 Cruze 2LT, 2014 Malibu 2LT, 2008 Cobalt 2LT

  • jwallyjwally Posts: 71
    In regards to previous post#1347,1352.I changed the intake plenum which did have holes in EGR ports. Shame on GM for not making good to customers(hope to see classaction lawsuit some day). I still can't get car running. It cranks over but won't run. If I feather(pump) the gas while turning key it seems like it wants to run,also strong smell of gas and black puff of smoke out of exhaust. I don't have a fuel pressure gage or scan tool so I'm limited. I pressed the schradder valve in on fuel rail and get a small one second squirt of gas with key on. I never took out plugs because they were in too tight and were affraid of breaking.any suggestions are appreciated.
  • jwallyjwally Posts: 71
    I changed the fuel filter now I get a good stream of fuel when I press the schadder valve.I hear fuel pump come on when key is turned.Is there anyway to read check engine codes without a scanner?Car still will crank over but don't start.
  • jwallyjwally Posts: 71
    Well alcan was right on target.It was tghe spark plugs I had car towed to King Bear St James,NY who charged me a whopping $199 to change plugs and so call tune up.The only tune up was my wires just a little advise before you get overcharged(ripped off)listen to Alcan.
  • imidazol97imidazol97 Crossroads of America I70 & I75 Posts: 23,199
    the service he provides here. He helped me without making me feel dumb. I cleaned my own throttle body - got rid of the sticking accelerator.

    His wealth of knowledge is appreciated here.

    2015 Cruze 2LT, 2014 Malibu 2LT, 2008 Cobalt 2LT

  • alcanalcan Posts: 2,550
    Well, if they used ACDelco platinum plugs (what it calls for) they're $13 and change each here in the Frozen North and not the easiest to reach, so that price isn't really too bad. Glad to hear you got it sorted out.
  • 2000 bonne ssei Part of the numbers display on the radio will not light. Can this be repaired? Thanks for any reply.
Sign In or Register to comment.