Pontiac Montana Engine Problems

beowulf58beowulf58 Member Posts: 12
My wife owns a 2000 Montana. The coil pack is bad and needs to be replaced. My question is, how does one get to it? I've heard that the engine needs to be rolled foward to get to the components in the back but I have never figured out how. If it wasn't for that, I would have it fixed by now.
I fix airplanes for a living so I'm quite mechanically inclined. Anyone know how to "roll the engine" or is there something I'm missing? Thanks in advance.


  • flm773flm773 Member Posts: 1
    Sounds like you need to rotate the engine. Here is info from my '99 shop manual on how to do this:

    1. Remove the throttle body air inlet duct.
    2. Set the park brake.
    3. Shift the transaxle into Neutral.
    4. Remove the engine mount strut bolts. Swing the engine mount struts aside (both left and right struts go from the engine to the front of the van).
    5. Install the J41131 (I used a pipe clamp on the engine to the front frame to pull the engine forward toward the radiator).
  • blg1blg1 Member Posts: 2
    hi i just bought a pontiac montana on dec 20 of 2006 it's has been in the shop since i bought it has engine problems such as low oil pressure it has enough oil and the service engine light kepis coming on the service center at the dealership they can't find out what wrong with it when the check the codes nothing come back with no problem. has anyone had this problem? it's been a nightmare since i got this montana :(:cry: :lemon: :lemon: :lemon:
  • beowulf58beowulf58 Member Posts: 12
    Join the club! Shortly after my first post, I found all my anti-freeze in the oil. Needless to say, it sits in my friend's garage while we take it apart trying to find out if the head blew or just the head gasket. In my research, it is a common problem on the 3.4 liter engines used in many GM makes.

    Blg1, my Montana has been in and out of the shop since we owned it. Yes, they always need something and they get alot of "Ghost codes." You know, codes that are there but aren't? If it wasn't for the cold, I'd be in my old 1970 Dodge Challenger. An engine without a computer is an easy engine to troubleshoot. Yes, I look foward to getting rid of the Montana.
  • blg1blg1 Member Posts: 2
    i just got my montana back from the shop. they told me they had to recalibrate the computer. well see how long that works or maybe something else will go wrong i hope not
  • dsgentilidsgentili Member Posts: 2
    Having the followig problems, all of which happen sometimes. Sometimes when I start it the car idles fast. Sometimes if I turn it off and then on again it will idle normally, sometimes not. Sometimes when I drive I take my foot off the accelorator and the car doesn't slow down, sometimes it will even speed up. Sometimes from a stop the car hesitates and "bucks" when accelerating. Sometimes on the highway the motor will rev for just a second, then go back to normal.

    Most strange, twice in the past 6 months, both times at highway speeds, the gas guage has gone from full to empty in just a few minutes. I stopped the first time to see if I had a leak in my gas tank. I've had it into the shop 6 times. They cannot get it to "act up" when it's there and don't have a clue. Thanks for the help.
  • jegjcjegjc Member Posts: 2
    is your gas filter new ? is there gas restriction (pinch some where) ?

    injectors clean ? Loose wire in the control pannel ?

    many question in fact can put you in trouble :)

    byeee jegjc québec city canada
  • dsgentilidsgentili Member Posts: 2
    Will try filter and cleaning injectors first. Thanks for the suggestion.
  • ejg80sejg80s Member Posts: 4
    I have the same gas gauge problem with my 1997 Trans Sport Montana. It usually happens when it gets below 1/4 tank and then the gauge pegs out to full. Does not happen all the time.
  • beowulf58beowulf58 Member Posts: 12
    Well, All, it took me awhile but I re-built the upper half of the engine in my friend's garage and it's been running pretty sound.
    I did, however, get yet another engine code. (No surprise, really) The emissions systems in those things are touchy. Being that I have two other small cars, my wife and I drive those most of the time and leave the Montana home as it's still a gas pig.
    Being that my two Hyundais are great little cars, I intend to stick with imports in the future.
  • mlkuttermlkutter Member Posts: 4
    :mad: Noticed a coolant leak and now the low coolant light is on all the time, even when the coolant is full.
    Engine is running hotter then before but not red. Will heat up as it idles and cool down as I drive.
    Is this a ticking time bomb or will I be OK if I keep the coolant full?
    Really can't afford any repairs.
    Need to drive out of town soon.
  • beowulf58beowulf58 Member Posts: 12
    STOP DRIVING THE VEHICLE!! That's where my problems started. Have someone who knows cars (a friend, preferably) take a look at your intake gaskets, in particular to the right side as you face the engine. As I understand it, it's a common problem for the Montana/Venture and the 3.4 litre engine. I won't lie, it won't be cheap. If I were you, I'd get rid of the vehicle. I'm trying to get rid of ours.

    As for mine, it has again broke and it now sits in a field at my in-law's house. I refuse to fix it again. The wife wants to and understands that it will be all her this time.
    If some kid wants it for a project, I'll take payoff of the vehicle.

    BTW, it's the last domestic car I plan on buying. Every one I've ever had has been nothing but trouble.
  • hawkeye56hawkeye56 Member Posts: 1
    I have replaced the intake gasket on my 1998 montana. same engine, 3.4 litre, nice engine, good power, bad intake gasket. then i replaced the water pump. and struts and front light lens' and the grills are both broken out, and the rear wiper and washer plug have be removed by unknown sources, (may they toast in hades)and does anyone else notice that the dashboard tower where the radio, heater and acc. switches are located gets to be about a thousand degrees after driving for about 1/2 an hour. i love my montana, i really do!!! :D
  • terry12247terry12247 Member Posts: 1
    I have a 1999 Montana. My engine light recently came on, which it does a lot if the gas cap is not on tight. I tightened the gas cap, that didn't help. Now it stays on and when you accelerate the engine light flashes on & off. It seems to be kind of sluggish and also when you sit with the engine idling it doesn't idle smooth. So far it's been a good car, but I'm wondering if anyone has had the same problem at all and what you had to do to remedy this problem. Any suggestions would be appreciated.
  • minivanh8rminivanh8r Member Posts: 5
    Whoa, I know you posted a while ago, but I hope you stopped driving the vehicle immediately. In GM vehicles, the "service engine soon" light most often amounts to a $50 part + $300 mechanic bill. If you have a very serious problem with a GM vehicle, the engine light will blink. You've probably figured this out by now though.
  • lisartlisart Member Posts: 5
    I have a 99 Montana, 159,000 miles on her. This morning I got in it to go to work and I had no electric. fiance jumped it and it worked fine for the rest of the day and now it's down again.
    He thinks its the alternator since its original I think its moisture. not sure where to start though.
    Replaced the battery last year, no issues with things being left on since they are all automatic.
  • beowulf58beowulf58 Member Posts: 12
    Ensure that all of your battery connections are tight. Even one loose one will cause problems like this as you're not getting a good connection. If you want to test your alternator, start the vehicle and then disconnect your battery. If it still runs, the alternator is good. If you have a volt meter at home, test the alternator and see how much voltage it's putting out. It should be around 13-14 volts or so.
  • katsmeowkatsmeow Member Posts: 1
    ya i have a 2002 pontiac montana over heats idoling and in town going out of town it goes down to a good temp we have replaced water pump and thermastate twice and head gasgets flushed the radiater too now we need to figure out how too get to the heater core does anyone knows i would much appreciate it Kathy
  • jhirneisenjhirneisen Member Posts: 64
    For all of you who have had problems with DEX COOL (including me) in Montana engines (and the other 2 GM sister mini-vans, and several other GM cars and trucks), there is a proposed CLASS ACTION SETTLEMENT. GM does not admit any problems, but it looks like they will have to reimburse effected owners.
    See this web-site:

    Jack ....in Colorado
  • lisartlisart Member Posts: 5
    if you still have this vehicle i would hope that by now you had the fuel filter checked cause that was my problem when it was sluggish as you describe.
  • kimmer827kimmer827 Member Posts: 1
    Jack, thank you for this info. I am SO not a car person, and have no idea what I'm talking about, but here goes. We have had our 2003 Montana to the mechanic twice for the same problem. The bolt that holds the rocker arm down strips and the engine light comes on and the vehicle runs sort of shaky. Both times it happened, we took it to the mechanic immediately and he says it's defective parts. I called Pontiac Customer Service and they want me to take it to get it diagnosed (for $72/hour) at a local dealership. I called the dealership and it would take them about two hours to check it out, minimum. My husband and I decided not to pursue it because we thought they would say it wasn't their responsibility. Is this at all related to the DEX COOL issue? Thanks for posting what you already did, and I'll watch for your reply.

    Kim.... PA
  • beowulf58beowulf58 Member Posts: 12
    I didn't know about this lawsuit. Unfortunately, I'm not a citizen of Missouri. If I was, I'd sign on to reclaim the $3000 I spent for an upper engine rebuild because of failed intake gaskets.
  • beowulf58beowulf58 Member Posts: 12
    I haven't changed that in awhile but I guess that's not a bad idea. It's not running sluggish. I just have an "eternal engine light."
  • woolverton7woolverton7 Member Posts: 3
  • woolverton7woolverton7 Member Posts: 3
    We have a 2000 Pontiac Montana. There has been a faint ticking sound under the hood for some time now that was hardly noticeable. There is oil in the van and we do keep up on the oil changes, however there is a slow oil leak as indicated by the spot in our driveway. The other night we drove the van and a security light came on which we had never seen before. The next day the van would not start. Out of the blue we had a dead battery but don't know why. We jump started the van and drove it to get the battery replaced. Now it starts but that ticking sound is MUCH louder now and can be heard well even sitting inside the van with the windows and doors closed. The ticking occurs immediately after starting the van. It is always there and increases with acceleration while driving and in idol. We are suppose to be driving our van on vacation in 3 days but now don't know what to do. Any idea what could be wrong, how easy it would be to have it fixed and how costly it would be?

    Thank you for your help!
  • tlcthistlcthis Member Posts: 2
    minivanh8r hit the nail on the head.

    We have a 99 and have had the intake manifold gasket (just slipped in under the warrenty THANK GOD $$$$$) a few years after that we had to have the head gasket replace.

    Someone correct me if I am wrong I am hearing it is actaully the coolant that GM is using along with the gasket design. Supposibly the gaskets have been redesigned the gaskets where actually melting.

    It is just so frustrating we have been running cars for how many years (never had gasket issues like this) now and they just want to change things around at our expense. That is not to mention that rust issues are still as big of a problem as they are.

    I agree with a presious post this will be my LAST domestic vehicle!!!!!! They do not want to admit (take care) of a problem unless several hundred people have died over it.
  • lisartlisart Member Posts: 5
    Well I was right sort of. It was electrical but it turned out that it was my brand spankin new battery then. Since I have had to replace the battery connection since it was arching under the van frayed connections.
    we are now at 170,000 miles and I still love my montana I'm sure at some point in will start costing me $$$. My only pain has been the passanger rear light. I have had to replace the wiring harness 4 times now.
  • honeydipperhoneydipper Member Posts: 1
    2003 Pontiac Montana 4.3L series \"E\" engine. Rocker Arm bolts (8mm) stripped out of the 1,3,5 cylinder head at 85,342 miles. Dealer repaired at $1,500.00, Dealer also checked the 2,4,6 cylinder head. Dealer verified 2,4,6 cylinder head and rocker arm bolts ok. 88,702 miles and ... yes, the Rocker Arm bolts (8mm) stripped out of the 2,4,6 cylinder head. Another $1,500.00. After some Internet searching found other Montana owners with the same issue. Makes me wonder if I searched for issues with GM 3.4L engines if I would come up with the same issue.
  • tigeroverflowtigeroverflow Member Posts: 4
    Request for recommendations to "fix", or trade-in???
    I love the van; acquired from dealer in November 07. It did a 12,000+ mile road trip then developed overheating problem intermittantly, which has gotten increasingly worse. The first signs of something was the sytem light would also be on for about 3-4 minutes on start up, then off for remainder of any outting, until the engine was shut off and then on restart, the light again would do the same thing, etc. Had in to very trusted mechanics garage, and it always seemed to never act up at the shop, so problem couldn't be isolated. Mechanic would blow out the line, thinking maybe air had gotten in somehow? Van would be "fine" for 1-2 days, then problem would repeat - while it would idle "fine" for over an hour at a garage when mechanic would test, for me when I'd pick up the van, drive about 5 miles, problem would resurface - idle at a light and it would start to overheat, or on an uphill. Van has been stored three months between Dec -07 - March 08, then July 08 - October 08 (no one driving). When I picked up the van in October, coolant level was "fine" - drove about 45 miles, parked, and two days later, overflow tank empty. But, since it was refilled, it hasn't seemed to leak anywhere. (level not dropping). Van is driveable at this point about one mile, without the temp line rapidly approaching the red zone. Mechanic has replaced thermostat, and problem still exists. Pontiac dealership here put it on a diagnostic scope and said "third cylinder is misfiring", "problem with oil pressure gauge" (didn't know what the problem is) and "can't control the fans with the scope - and we should be able to do this". The Pontiac dealer guy couldn't say 100% for sure it is head gasket. Didn't know. Thought fan motor should be checked out. I've had it two mechanics who say fan motor is "fine" as it isn't acting up for them. Van with engine running, most of the time the heat won't kick in for about 30-45 minutes, then it'll be like the fans "cough" and then all of a sudden there is a nice blast of hot air, and the heat stays on.
    Engine has 77,000 miles on it approximately and intake (valve?) thing was done, according to last mechanic.
    Read your forum pages and it is mentioning a "hydro carbon test" . I'm a not a mechanic - in layperson's terms - 1) what is a hydro carbon test - is it something I can do - or - how is it done? 2) I saw some things in a forum for Acura's. It mentioned doing a "compression test", and checking oil to see if it looks like runny milk, chocolate (= blown headgasket) - is this true for a Montana van, too? 3) I also saw mentioned doing a "leak down test" - How is this done? Is it relevant to a Montana van? 4) Fan relay -- is this the same as the fan motor - and does it sound like this might be causing the problem?

    Rates: I am being quoted $79/ hour shop rate and 18 hours for labour, + parts. Estimate is about $2500 to do the job. How much should I be expecting in labour hours and if it is a blown gasket, what are normal rates for machining / grinding of flat heads, and should the water pump be done, too? Could the water pump, alone be making this problem?

    I've been told the belts are "fine" - and didn't ask if this means the "timing belt", too. Is this an easily accessible belt - that likely was checked as well?

    I have the additional challenge - the van hit the tow-only level in Canada, and is licensed in the US -- so I will need to tow it back to US if I can't get this resolved. I live in Canada, "business" in US (van is used for nonprofit in US).

    Can a van in this condition be "traded in"? Our nonprofit isn't in a strong cash flow position to deal with trading in - so would like to fix, if possible, and it makes sense to do so.

    Thank you to all you trusted mechanics out there, or dealership service departments who can give some coaching on this. We love the van - - and it works well for what we need it for! Just really don't really want to trade in, unless to get the newer model of the Montana.

    :confuse: :sick: :cry:
  • beowulf58beowulf58 Member Posts: 12
    That sounds much like what mine was doing but it wasn't the head gasket, it was the intake gaskets which are notorious for going bad in these vehicles. With the help of a friend, I replaced them instead of paying the $2,500 to have someone do it. If you and/or someone you know can fix this problem yourself then you will be in it for about $200 worth of seals. It's time consuming but you'll gain alot of knowledge in doing it.
    If you just want to get rid of it, you won't get much for a vehicle with an engine problem, especially with the price of gas and a vehicle that isn't fuel efficient IMO. Either way, you're options aren't too appealing.
  • tigeroverflowtigeroverflow Member Posts: 4
    Hi, Beowulf58,
    Thanks for your input. I am checking on your point -- I believe the last mechanic said the intakes were "done" already. He pointed out to me, to areas on each side of the metal-looking thing in the middle of the space under the hood (gee, I sound like such a girl saying it this way -- but I know it wasn't the rad, but I don't know if that was the engine?) Anyway, he said those two things, one on each side were "done".

    And - - I will call him to check on this.

    Do you know how to run a hydrocarbon test?


  • tigeroverflowtigeroverflow Member Posts: 4
    Hi, Beowulf,

    Just a quick update - I went down and did my own check on the van, which is parked outside the mech's garage....oil is "clean", and rad isn't splashing back coolant when engine is warm. Intakes were "done" (dealership done - before I got van).

    Do you know anything you can "share" about fans and fan relay or the piece that attaches to waterpump -- could this be causing the symptoms for overheating?

    Talked to mechanic today -- same shop / other sr. guy - he doesn't think it is the water pump...(but he's guessing).

    Plans to do htdrocarbon test and pressure test Monday.

    I keep feeling like it is maybe one of the fans not kicking in properly -- but I don't know if this is they relay(?) or the fan...? It seems one fan definitely runs, as it blows cold air. Then suddenly something seems to "kick in" (like an engine "cough") - perhaps the other fan????


  • beowulf58beowulf58 Member Posts: 12
    Don't worry, Tiger, I won't pick on you for not knowing what something is. I do like how you pick on yourself though. Anyway..

    If your mechanic says they were done, I guess it's a matter of how much you trust him. From just pointing it out won't do much since the seals are sandwiched between the valve covers and the head. Hopefully whoever replaced them did NOT use the anti-freeze that GM used. It is believed this contributes to the wear down of the seals.

    No, I don't know how to run a hydrocarbon test. My guess is plugging a code reader in will tell if their are any emissions issues. They are quite easy to use and if you have a book, which I do, it will tell you what the problem is and what is needed.

    Hope this helps.
  • beowulf58beowulf58 Member Posts: 12
    Sure, a bad fan can cause overheating. Electric fans run on a relay that turns them on when the water temp reaches a certain temperature hence the warning near them that says, "fans may turn on at any time." If you have a bad relay to them, it's the same effect. If it fails, it may not turn your fan on at all. You have two fans, one is the cooling fan which is automatic, based on engine temperature, and the other works when you use your air conditioning.

    The water pump is it's own part and is mounted into the engine block. It does just what it says, pumps the fluid around the engine. A fan won't affect it, at least, it shouldn't.
  • mhaistmhaist Member Posts: 1
    hello, my belt has been slipping from the harmonic pulley, Now i have had the car for 4 years and replaced the belts a few times, i changed the belt tensioner and that did not fix the slipping. im wondering if the original owner but the pulley on backward what do you think?

  • greyduke3greyduke3 Member Posts: 2
    i have a 2001 and it runs good but wont idle.I replaced the throtle position sensor and idle air control valve
  • SoonerTideLadySoonerTideLady Member Posts: 1
    We have changed pulley after pulley the water pump has been changed the power steering pump has also it just got changed the other day and after it got changed it is sluggish to start up and it still squeals really bad i was told that it might be the alternator, i really don't know what it could be could someone please help? thanks for your time.
  • greyduke3greyduke3 Member Posts: 2
    wont idle ive changed the throtle postion sensor and the idle air control valve.please help i dont have any thing to drive. :cry: :confuse: :cry:
  • 4steri4steri Member Posts: 7
    You need a new harmonic balancer. The pulley is slowly slipping, pulling away from the balancer (rubber). It's not align with the other pulleys, which is causing the belt to slip.
  • havnfun2havnfun2 Member Posts: 2
    My Moms Montana did the same thing....go and get a Throttle Positioning Sensor for about $35... they tried to tell her it was the intake gaskets leaking and wanted her to pay $1800....she called me and I told her it was the TPS and since we replaced it she has had no more problems with her van speeding up on it's own...hope this helps if you haven't already figured it out.
  • tigeroverflowtigeroverflow Member Posts: 4
    Thank you for your posting. This would have been an interesting thing to look into. After mechanics were split as to what was causing the problem, it was recommended by "all" to trade in my much-beloved van. So, after it overheated on the freeway - during a test drive related to the trade in (!!!) I really had to trade it if possible and did. The GM dealership gave me full value and a good price on a Chevrolet Uplander 2006 w/ low miles. It is NOT the van the Montana was - so miss the Montana! An almost loaded Uplander is a bad joke compared to the Montana - so many things missing, lower power, just everything. But for now, will hang on to the van, for timing of other things in life issues. Bigger picture - if the used car economy was a stronger market, I would get rid of it for a Montana - even an older one. Got the Uplander in December. It is going into the dealership for more repair work - for I think this is the 5th (!!!) time. Problems with gear shift getting stuck, horn still doesn't work, had a nearly broken tie rod that dealership didn't fix before selling the van, and the list goes on. Thankfully, other than wasting time, it has a happy ending since I bought the most extensive full five year extended warranty. For anyone listening to this - get the warranty. At $2000 it is a bargain! Less than six months into this - if I had had to pay for all these repairs out of pocket, I would have been out of pocket at least another $500 by now. The warranty covers first dollar - so I have had no additional money paid out. Meanwhile, Pontiac Montana - the model I had - wonderful van. Should have just put the $3-4000 out and fixed it, hindsight.
  • chiebutchiebut Member Posts: 1
    hi! i've had 2000 montana the problem is when i'm driving it all the guages shuts off and when i move the steering wheels it goes back! and my fuel gauge is unstable int goes up and down and most of the time is always full even though it's not! need help!
  • kenniekennie Member Posts: 38
    Re the fuel gauge... this is very common in montanas... mine has done it for 3 years and it's a 2000. Just use the odometer to indicate how many Kms you've gone and then fill up... the cost to fix just is not worth it unless you have warranty. I believe the "LOW FUEL" light is indiependant of the gauge problem so when it comes on you are definately low in the tank on fuel... this is the way mine works. You would have to have the fuel sending unit replaced and it is located in your gas tank very likely... they can test that is is failing by testing the wires.. if certain voltages are read they can tell it's gummed up. Cleaner can be poured in the gas tank to attempt to clean it but i'm not sure if it is worth of the risk of plugging something or running such cleaner through your engine if you don't absolutely have to.. the cleaner I think is called sea-foam I think. Cheers.
  • ray80ray80 Member Posts: 1,655
    Also for the fuel gauge (I believe its applicable for a 2000), it may be an issue with the c-305 connector.
  • kenniekennie Member Posts: 38
    What is the c-305 connector and what does it do??
  • ray80ray80 Member Posts: 1,655
    Its a pass-thru connection for wiring (from inside cabin to outside/underneath). It connects various wires for things in rear of vehicle(including connection to fuel pump/sensor). While its weatherproof on bottom (underneath) it is not inside cabin, spills/ various leaks inside can cause water intrusion and subsequent corrosion of wires. Google ' gm c305 connector' and you will find lots of stuff.
    The connector should be under carpet to the rear of drivers seat (you may be able to see exactly where by looking under vehicle for a bundle of wires that come out from cabin)
  • tina2237tina2237 Member Posts: 2
    So what does it mean when your "service engine soon" light stays on? I am having a new issue with my van and it is staying on.
  • tina2237tina2237 Member Posts: 2
    I was driving home and my van all of a sudden lost power and kinda sputtered. It almost felt like I was running out of gas. I knew that was not true since I just got gas. There was no loud bang or anything. So I pulled into the next driveway and my check engine light came on. So I turned the van off. I got out and checked the water and oil and everything was fine maybe 1/2 quart low on oil. Engine was not overheated and no leaking oil or anything. I turned my van on and there is a clicking noise coming from the engine and it has loss of power for sure. So I am going to have to have it towed. Does anyone have any idea? Has this happened to anyone? It is a 2003 Pontiac Montana with 115000 miles and has been taken care off well. so I am a little confused. I hope someone may have some answer? Thanks
  • spike99spike99 Member Posts: 239

    From your statement of "there is a clicking noise coming from the engine", your high miles van (for a 3.4L engine) could have anything from blown main bearings, to broken cam to blown pistons. It all depends on the exact sound of the "clicking" and its sounds location under its hood. Best is to get a certified mechanic to investigate and confirm what could be broken.

    Also... "Do trust your gut" as well. If your van has NO rust, its tranny is still good, its steering is still firm and overall, it's still a sound vehicle, then it might be worth fixing. Fix with new engine parts (on existing engine), or perhaps fix with a new re-built engine block. But if your vehicle is near its "end of life" and engine repair/replacement is too expensive, then simply "write her off". One of those "Humpy Dumpty fell off the wall" things....

    Hope this helps....

  • 07outback07outback Member Posts: 1
    My wife just had the same problem happen to her 2003 Montana on the way home from work last week. :cry: We have 98,000 on the van and we have done all of the regular service to it. Now we are trying to figure out what to do? Does anyone have any recomendations? :confuse:
  • lisartlisart Member Posts: 5
    have your fuel filter checked, mine was almost completely clogged
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