Consumer was advised the engine failed due to a design problem of the intake manifold. The top of intake manifold was plastic and had a metal tube that ran through plastic. Over time the plastic also degraded and cracked which resulted in the coolant entering the engine.
1998 Pontiac Bonneville engine complaints
Page 6 of 8: complaints 131 to 160 of 200, newest first, as owners wrote them.
My complaint is: I was driving down illinois interstate highway 55 at 70 MPH when my engine died, because my manifold keeps cracking, this is the 4th time!! Because my engine died, it kept blowing and forcing antifreeze down my intake and filling my cylinders with water and antifreeze, causing a vapor lock!!! I tried to restart the car in neutral going 70 MPH, with 20-25 cars around me and 3-5 semi trucks, but the engine was locked up!!!! I lost control of my car!!! I had no power steering, no power brakes, no control to be able to avoid a 20-25 car pile up, with tens to hundreds being injured!!!!!!!!! This is a "safety issue that must be resolved!! Gm needs to do a complete recall of all 3.1, 3.4 & 3.8 v6 engines made with plastic manifolds and plastic gaskets!!!! Gm needs to replace them with the aluminum manifolds and rubber gaskets they used to place on "all engines manufactured since these changes", which I believe is 1995!!!!! Also, do not allow gm to deny these charges of defective material, parts, workmanship, or manufacturing, because I was told yesterday there is a "new technical service bulletin" changing the manifold, gasket and installation!! Please see the attached url - http://www.petitiononline.com/mod_perl/signed.cgi?gmcnsmrs to view the over 1,300 people so far that has been identified in just a few months by word of mouth. The dealerships stock these parts, where before their design change in 1996 from aluminum to plastic manifolds, the dealerships never stocked these manifolds!!! Other support websites: http://www.geocities.com/gm_intake/index.htm#updates & http://www.gm-v6lemons.com
1998 pontiac bonniville they use a plastic intake manifold cover of schrowed.within this cover they have hole for the egr valve which gets very very hot,and to cool this they run coolant around this within the plastic. Don't they realize that the plastic will crack from expansion and contraction and coolant will infiltrate the intake manifold and the entire combustion chamber,exhaust. This happened to my 98 bonniville and I want this to be investigated.
The plastic intake manifold failed allowing coolant to enter the cylinders and oil, causing damage to the engine exhaust. Gas from the egr passes through the plastic and eventually softens and deteriorates it. This has been an ongoing problem with this engine according to local dealers and mechanic. Why hasn't a recall been issued since it is a major safety and damage issue. I called the manufacturer---no satisfaction. *****dims 11 ivoq entry posted after 12/12/02 cut-over to artemis******770815. *ak
Car suddenly began missing and running very rough. Drove only a short distance & car stopped running. The dealer said the upper intake manifold plennuim needed replaced, as well as the plugs removed & cleaned. Also needed oil, filer & collant changed. Cost over $750 to repair & manifold was about the only engine component to not be included under the add'l service contract we had purchased.
Consumer states the plastic intake manifold cracked, causing engine to hydrolock and bending 5 push rods. This allowing coolant to enter engine causing major damage. Ts
While in motion, the engine died causing a pile up on the highway. The engine manifold and the gasket caused what is called a vapor lock up. This is a continuous problem with this vehicle. The manifold and gaskets have been replaced 4 times prior.
No summary. Dt
Consumer advised that while driving the intake manifold cracked causing coolant to leak onto engine. Vehicle stalle oh highway. Ts
Upper intake crack which caused coolant leak into intake and fuel system. Dt
The engine intake plastic manifold cracked, which caused antifreeze to run into the engine. Dealer has been notified. Ts. *jg
Consumer states that while driving at any speed and no warning coolant fluid are being pump into the engine. Dealer notified ts
While traveling on the highway and without prior warning the check engine light came on the dashboard. The intake manifold melted causing oil to mix in with antifreeze vehicle shut down. Ts
Vehicle stalled while driving on a busy interstate. The dealer stated the problem was the plastic intake had cracked, which dumped the engine coolant into the chunders and locked the engine. Mr scc
Consumer states while driving vehicle started to make a wierd noise, vehicle started to loose power and engine died. Cause is unknown. Please provide any further information. Nlm
Engine light illuminated. Pulled over and noticed water leaking from radiator. Upper plenuum plastic melted, allowing water to get into engine, and engine locked up. Please provide any further information.
While driving vehicle stalled out. Had vehicle towed. This was a result of coolant fuel leaking.dealer contacted.
Engine lost coolant - informed by dealer that intake manifold had warped allowing coolant to mix with fuel and air. Dealer said that this part was a plastic composite part that failed often. Failure could cause engine loss or fire. Intake manifolds are not supposed to warp under normal conditions. *ak *ph *nlm **dimsii ivoq entry posted after 12/12/02 cut over to artemis**765826
After refueling engine light illuminated. Took vehicle to dealer, dealer stated radiator needed water. Water was coming through radiator, and exiting through exhaust system. Please provide any further infomation.
While driving vehicle started running rough. Then, the engine stopped. Contacted dealer, valve cover gasket was leaking, and water went into engine cyclinder. This is a common problem. *ak the mechanics removed/replaced the intake manifold, both upper and lower manifold gaskets.
Anti freeze wad sleaking but not on ground. Dealer was contacted, and noticed anti freeze leaking into engine, intake manifold needed to be replaced.
Engine would not run due to coolant in cylinder/s, cost to replace plastic intake manifold apx. $900.00 the term degrade as used by gm should be defective as by all experience, an intake manifold has no moving parts to wear and the car was equipped with coolant which does not need replacingg until 150,000 miles or five years. There is no maintenace that any owner can do to prevent this from happening. If it happens when in traffic and the engine stopped, there will be serious safety problem. Gm does not want to take responsibility for a defect or design problem.
While driving and without warning, engine stalled, resulting in vehicle becoming inoperable.*ak consumers wife was coming to a stop when the engine froze. The vehicle lost all coolant and radiator water due to the plenum melting from the egb tube. The poor design has been corrected by gm, but as a repair bulletin and not a safety recall.
Consumer was traveling on highway and smelled a rotten smell coming from vents area., and without prior warning, vehicle shutdown inside of parking lot.
Consumers vehicle experienced an engine coolant leak.
Consumer states the engine blew while driving.
Engine (intake manifold) is defective. Leaking coolant into engine. This is the second 1998 bonneville v-6 we've had this happen with. The first one the engine had to be completely replaced, since it was burning coolant in the engine and into the surrounding air. This bonneville is currently being looked at and will need the intake manifold replaced, possible the entire engine as well. Pontiac issued technical sales bulletin 01-06-01-007 in july 2001 knowing they had this problem. They should recall this badly designed engine that can cause engine lockup and coolant smog release into the atmosphere.
While driving 10-15 MPH, engine was hesitating. Consumer noticed a burning smell. Dealer determined that plastic intake manifold had a hole and was leaking fluid onto engine. Engine had to be replaced. *ak
On 8/25/2000 had to have my water pump replaced($536.91). Picked up car went 11 mile it quit had to be towed back to performance pontiac. Informed at that time the plenum failed cost of that job including towing an rental ($830.80). On 3/20/2002 car quit had to be towed in to performance pontiac again. Cause of the problem the plenum failed again. When I called gm pontiac division they said there is nothing that they can do because of the mileage of the car. I do not believe that is the issue. It's a $31000. I travel for a living and have the upmost respect for my vehicle. I have all my records of my maintenance that would amaze you. The car has never been over 3000 before each oil chg. Tires are rotated every 5000 miles. Transmission oil chgs has been done twice. Brakes have been repaired twice prematurely to prevent serious damage to other parts. I can provide you with records that show to the penny what I've spent on gasoline from the day I bought the car. I am convined that it is not a mileage issue and totally convinced that this is not a result of any negligence on my part. I was totally turned off by the attitude of pontiac concerning the problem with this part. I can also provide you with testimonials from businesses that I use to service my vehicle to what a fanactic I am about preventitve maintenance. Waiting anxiousley for your reply. Thank you for listening. Nick leogrande.
Have replaced plenum, head gaskets and is currently in repair for rods. Recommended new engine. With new engine, repairs total $6000.00. Nlm
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