Design flaw of coolant pipe. Breakage of the coolant pipe inside the air intake of the 3800 v-6 engine causing engine coolant to flood the engine and cause immediate engine failure.
1998 Pontiac Bonneville engine complaints
Page 4 of 8: complaints 71 to 100 of 200, newest first, as owners wrote them.
Consumer took vehicle to dealer to be inspected, and mechanic noticed that the plastic intake manifold cracked causing fluid to leak onto the engine.
I too had a intake exhaust manifold failure !! Leaked anti-freeze into cylinders !! But mine was caught in time !! Took to dealer the day the check engine light came on !! Intake manifold replaced, fuel pressure switch replaced, plugs and plug wires replaced !! Dealer ship owner said "this problem did not surprise him" there has been enough of these problems documeneted on your site !! Are you ever going to do something about the problem?? Cost me $ over $700.00 mike miller laporte indiana this car only has a little over43,000 miles on it !!
Engine stopped on interstate. Car was towed. Failure analysis indicates intake manifold failed allowing engine coolant to be drawing into engine causing hydrolock. Car had about 60,000 miles. Have found numerous other owners of other gm cars with 3.8l v-6 engines with same problem.
Engine/cooling system.
Intake manifold leaked coolant into engine. Seems the plastic intake manifold and gasket warped causing excessive coolant consumption into the engine.
Consumer bought the bonneville in august, since then it has been in repair shop 7 times. The first four times were for transmission failure. They replaced the pressure control valve and throttle body. The remaining visits were for 4 fuel injection system failures, injector coil failures melted 4 spark plug wires. Also, water pump started leaking.
Dexcool coolant corroded an upper plenum intake costing me $1,1185.00. This pontiac bonneville only has 69000 miles on it. My mechanic says gmc is aware of the problem and is doing nothing about it.
On november 4, 2003 my wife contacted me at lunch time to inform me her car would not start. After checking the battery and starter it was determined the motor had locked up. When I contacted the dealer I found that I still had 1 year left on my extended warranty although at 88,000 miles I was 500 miles over the extended warranty. They informed me this was classic signs of the air intake manifold. I proceeded to repair the car myself. After taking the air plenium off the air intake manifold I found the top of the air intake manifold filled with anti-freeze. Apparently, the air plenium had developed a crack and allowed the anti-freeze into the air intake. This permitted anti-freeze to fill number 1 cylinder with anti-freeze and would not allow the piston to travel to the top of the cylinder. After searching the internet it became apparent I was very lucky. There were several cases reported on line where this happened while people were driving and caused major lower engine repair such as shattered rods and crankshafts. I also noticed there appears to be a large number of complaints on your web site on this issue. I sent an email to general motors via their web site on this issue. It amazes me that this part is made of a plastic composite material and is mounted to the top of the engine. With the heating and cooling cycles the engine goes through, it is only a matter of time before this product would fail. From what I have seen on the internet and talking to various part clerks it is between 80,000 miles and 100,000 miles when this product fails. I am not sure if this is designed intent by gm, although they have not changed this design through the 2003 models. Needless to say I did not get a response back for gm. I felt with this type of defect and the safety problem this could cause if this were to have happened while traveling down a major highway there should have been a recall on this. Sincerely, william j. Fitzgerald.
Noticed slow loss of engine coolant (no obvious leaks) over the month prior to incident date. On incident date, engine popped, banged, and ran extremely rough on start-up. I had read about a problem with the 3.8 liter v-6 gm engine, and brought vehicle to dealer. Dealer found warped/cracked plastic intake manifold, which was replaced at a cost of over $700. Pontiac/gm would not consider any cost sharing on the repair. Failure was in area of manifold/plenum where throttle body/egr valve mount, and is due to excessive heat build-up over time. This problem is a design defect (use of plastic manifold vs. Metal in high temperature application) on this and several other gm v6 engine types from 1995 to at least 2002. Gm installs these engines in various models of pontiacs, buicks, oldsmobiles, and I believe some chevrolets. I estimate that gm has well over 1,000,000 of these problem engines in vehicles, and their potential cost liability is in the billions of dollars. I don't expect them to initiate a recall without government mandate. In other cases I have researched, this problem has apparently LED to complete engine failure, and in some cases, engine compartment fires.
Vehicle's warning signal starts up and the vehicle hesitates or stalls out while driving.*mr the intake manifold was also damaged causing the vehicle to smoke and over heat.
1998 pontiac bonneville, 3.8 liter v6, 65k miles when its intake manifold "plastic" gasket warped under normal use. Coolant damaged it when drained into engine. Gm has several service bulletins out there regarding their 3.8-liter v6 and this problem. They know it's defective in their design, but refused to cover any percentage of repair cost. Luckily, the car was not traveling down the interstate and no one got hurt from a locked up or destroyed engine. Gm should recall or offer a repair copy on their defective design. Service bulletin replaces "plastic" part with redesigned aluminum one. They know its a problem, it's time they make it right.
On september 19,2003, my 1998 pontiac bonneville with 3800 v6 overheated(check engine light and high temp on gauges), would not restart and would not turn over by starter motor. Had to tow into shop and had cooling system checked. Pressure leaks were detected. The shop mechanic diagnosed that the upper plenum for the intake manifold, which is made of plastic, had become warped where the egr valve connects to the engine block. This allowed antifreeze to fill up the engine cylinders. The small repair shop where my car was repaired stated that they had replaced many of this particular upper intake plenum for this particular engine. The tow truck driver told me what the problem was even before I told him the entire problem.
Coolant was leaking from intake manifold into the engine. This could result in engine failure.
While driving vehicle overheated and blew out. Technician diagnosed plastic intake manifold cracked. Dealer notified.
Vehicle's intake manifold is defective.*mr the consumer is disturbed about the her vehicle not being allowed in the recall for defective intake manifolds. When her vehicle is experiencing the same problems mentioned above. She is now requesting to be reimbursed for approx $1299.56 to resolve this issue and avoid litigation.
Upper intake manifold developed cracks and anti freeze leaked onto the engine. This resulted in the motor locking up.
This car has had very good care/maintenance, has not been driven hard, and has only 67,000 miles on it. While driving down a city street, approximately 35 MPH, the car began to sputter. I pulled in to a parking lot and shut the car off so that I could look at the spark plug wires. I had a spark plug wire loose when this happened once before. I had no over temp, I had normal oil pressure and there was no check engine light illuminated. I did not find a noticeable problem, but I could not get the engine to start again. I had it towed home. I changed the battery, the starter, and finally checked to see if the crankshaft would turn, which it wouldn't. I removed the spark plugs and tried it again. I got antifreeze from four of the cylinders! This was determined to be because of a failed intake manifold gasket.
Consumer called complaining about antifreeze leaking into the intake manifold. Manufacturer and dealer were contacted, and stated that there was a recall on a different vehicles with the same engine but not on this particular one.
The consumer was driving 20 MPH around a corner. When the consumer attempted to accelerate the vehicle began to buck, the check engine light illuminated and the car suddenly stalled. The dealer diagnosed that the upper intake manifold gasket failed. *nlm the plenum failed and caused coolant to enter the engine. The engine hydro-locked due to a faulty gasket that gm had known about. The engine, starter and plenum was replaced. *scc
Coolant was sucked into the cylinders through two unknown holes in the intake manifold system. Engine had 66,000 miles. Resulted in total blow-out of engine and replacement was necessary at a repair cost of close to $3,000. According to service technician this engine has a history of these problems and gm needs to rectify the faulty plastic manifolds and gaskets.
While traveling on the highway and without prior warning coolant was leaking into the engine, causing vehicle to overheat.
I purchased vehicle on 02/17/03. In may 2003, without any warning, I was replacing a motor. Once again, on july 19, 2003 I am replacing yet another motor.
Consumer called complaining about having gasket problems. Gaskets have been replaced twice, and he was concerned. Manufacturer was not contated at the time of this call.
Wife was driving car when she noticed the check gauge ligt came on. Engine started overheading. I went to location and added collant but something did not seem right. Called tow and had towed to dealer ship. Was told problem was between the egr passage at upper intake manifold! Otherwise called "material degradation". Dealership said this was common for this year of car.... Cost us approx $700 to have fixed. Called gmc customer satisifaction and did not get any satisifaction... Sold car and will never buy another gmc until they can stand behind their problems. Would like to see this recalled...
On july 1, 1998 pontiac bonneville with 3800 v6 overheated. Took it into shop and had cooling system checked. No pressure leaks were detected. When I left the shop, engine began missing and check engine light came on. Engine smoothed out, but took back to shop and they put on machine. Cylinders 1 and 6 had been misfiring, but seemed to be running fine. The next day on way to work, the engine began missing badly again and temperature gauge went up to about 240. After work, engine would not turn over at all. After having car towed back to shop, I learned that the upper plenum for the intake manifold,which is made of plastic, had become warped where the egr valve connects to the engine block. This allowed antifreeze to fill up the engine cylinders. The small repair shop where my car was repaired stated that they had replaced 10 of this particular upper intake plenum for this particular engine.
A plastic component in the engine of the 1998 bonneville melted allowing antifreeze to enter the engine and causing engine failure. There was only 70,000 miles on the car. All replacement engines have the same plastic components and can have the same potential for engine failure or fire.
I own a 1998 pontiac bonneville. The manifold covers are made of plastic and eventually crack causing antifreeze to enter the engine causing vapor lock. The engine shuts off leaving the driver with no power steering or start up capabilities because the starter cone on this incident was blown off due to intense pressure. My 17 year old daughter was driving at the time and I'm thankful that she was in town traveling only around 25 MPH. I dread the thought what may have happened on the expressway. I have heard of and read of several cases that are exactly like this one. General motors is aware of the problem yet refuses to recall this manifold cover problem. My vehicle is well maintained and has only 83000 miles on it. There is no way this should be allowed to continue to happen. It is very costly to myself as a consumer. It ran me nearly $900 dollars to fix this problem. Hopefully there isn't any long term damage (which I understand there will be) to my engine from this problem.
Consumer took the vehicle to the dealer since the engine light appeared on the dashboard. Dealer stated nothing was wrong with the vehicle. Four days later, engine blew out.
Consumer tried to start up vehicle, an under hood fire occurred. *mr the vehicle wouldn't crank. The consumer thought the vehicle wouldn't start because it was cold. The vehicle sounded like something exploded under the hood as the consumer started the vehicle. *scc
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