Manifold/header/muffler/tail Pipe problems of the 1999 Buick Park Avenue

Plastic intake manifold failure occurred on 1999 Buick Park Avenue with approximately 45,000 miles. Coolant leaked into the engine and resulted in a misfire code in multiple cylinders. Symptoms experienced by the driver were a rough idle at start for 30 seconds, and the service engine soon light would come on, sometimes staying on and sometimes extinguishing after 15 seconds. The car was immediately driven for service. The dealer initially diagnosed the problem as a combination of dirty fuel injection system (cleaned regularly, but still needed to be cleaned again to convince dealer to rule out this problem). When problem persisted in cylinder #6, the problem was then diagnosed as a faulty fuel injector which was replaced. When the problem persisted, it was noticed that coolant had gotten into cylinder #6 in small amounts and cause a misfire. Dealer then diagnosed problem as the plastic intake manifold. Web searching reveals that this is a chronic problem as the design was changed from metal to plastic. However, there are no current recalls on this issue. Cost to repair is approximately $1,700.

The contact owns a 1999 Buick Park Avenue. The contact stated that the warning indicator illuminated for the antifreeze. When he checked the level in the proper receptacle, it was empty. The vehicle was towed to the dealer and they replaced the manifold and catalytic converter. The antifreeze is still leaking. The current and failure mileages were 40,000.

The 1999 Buick Park Avenue has a plastic plenum that fails while the vehicle is in motion unannounced, causing antifreeze to enter the engine compartment, locking the engine up. Consequently, there is a total power failure. Power steering and power brakes do not work, and the car has no power. Can't coast or anything else. Consumer has been in contact with Buick, but, there was no recall. Consumer considered this vehicle very unsafe. Car just stopped in the middle of the road. This was instantaneous, and with no prior problems. Consumer took the car to his mechanic, and they replaced the plenum from gm products.

The intake manifold cover is made out of plastic, and has become defective for a second time. The antifreeze is going into the engine. . . . . . . . . . .

1999 Buick Park Avenue. Consumer writes in regards to defective plastic manifolds and requests reimbursement for two engine repairs. The consumer stated on July 28, 2003, the vehicle stopped running and again on November 13, 2014. The consumer stated both times, the manifold had to be replaced.

While driving the vehicle stalled and the check engine light illuminated. The vehicle was taken tot eh dealer where it was determined that the engine intake manifold had a design defect which caused premature gasket failure. That failure caused coolant to leak into the engine manifold and burn in the engine. The vehicles a/c compressor also failed.

When the consumer attempted to start the vehicle a loud explosion occurred. The explosion destroyed the upper intake manifold plenum, fuel rail and fuel pressure regulator. The consumer paid to repair the engine and other damaged parts. The dealer and manufacturer refused to reimburse the consumer for the repairs. The manufacturer has not determined the cause.

The engine exploded upon starting the vehicle. There was damage to the upper intake manifold (plenum), fuel injector rails, and fuel pressure regulator. All componets required replacement, plus a seal and valve kit. Both gm and the dealer refused to reimburse for the cost of the explosion and subsequent damage/repair.

Intake manifold leaked coolant fluid all over the engine. This resulted in the vehicle stalling while driving . The manifold was replaced, but the problem recurred. The dealership replaced the manifold with a redesigned one.

Crack developed in the manifold as well as in the upper intake plenum.

The plastic intake manifold melted, and caused coolant to leak onto the engine. Scc.