Coolant was leaking from intake manifold into the engine. This could result in engine failure.

- Hager City, WI, USA

Upper intake manifold developed cracks and anti freeze leaked onto the engine. This resulted in the motor locking up.

- Carbon, IN, USA

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...

- Holts Summit, MO, USA

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.

- Columbia City, IN, USA

I have a 1998 Pontiac Bonneville (GM 3800 liter V-6). The plastic intake manifold cracked allowing coolant to flood the cylinders and resukting in a $675 repair bill. Luckily this happened in my garage and not on the highway. No major engine damage. No fire; just a costly repair bill that I think GM should be responsible for.

- Grafton, VA, USA

While driving and without warning the intake manifold failed and caused the motor to seize. Dealer notified.

- Cookeville, TN, USA

When the consumer attempted to start the vehicle, it cut off. This was due to a failed intake manifold. Dealer was notified and part was replaced.

- Casselberry, FL, USA

The upper intake on the vehicle, leaked antifreeze.

- Brighton, IL, USA

I own a 1998 Pontiac Bonneville with 87,000 miles and out of warranty. Late one evening my car suddenly let out a cloud white smoke and stopped in traffic. I assumed that when the engine light came on and the manual suggested "a tank of bad gas" or similar problems that the problem was not serious. After having my car towed to my dealer, I was very surprised when my dealer informed me that the intake manifold had cracked and coolant had infiltrated my cylinders. This "minor" repair ended up costing $1836 after replacing the manifold, gaskets, hoses, and thermostat. I do not have much trust in my vehicle nor the automobile manufacturer who knows that this is a problem with my year and model of car and does nothing to warn owners of this problem. I feel that I should be compensated for the parts and labor to replace a manufacturer mistake.

- Hemet, CA, USA

The intake manifold failed.

- Garrett, IN, USA

The upper intake manifold cracked and leaked antifreeze onto the engine which caused the engine to lock up.

- New Castle, PA, USA

The upper intake manifold cracked and leaked antifreeze onto the engine which caused the engine to lock up.

- New Castle, PA, USA

I have had the plenium manifold fail in my 1998 Bonneville and have spoken to a dealer about this and tyey are aware of this problem but yet they do not have any plans to do any type of recall.the service dir. That I spoke with said they were having this problem with alot of the same style motors that GM put out but they have no plans on fixing this problem, but I had to spend $1100 of my money to get this problem fixed and the dealer just seems not to care that they have a problem.

- Richmond, VA, USA

The dealer diagnosed that intake manifold had cracked and leaked antifreeze over engine components. (related investigation EA02-030) ph the dealer replaced the upper manifold plenum. Scc

- Silver Spring, MD, USA

Consumer called complaining about having problems with the intake manifold. Also stated that while driving the vehicle the engine will overheat. Dealer was contacted and stated that he had a different intake manifold and it was replaced but consumer has the same problem again. The second time the vehicle got on fire.

- West Hartford, CT, USA

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.

- Hawthorne, FL, USA

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.

- Raleigh, NC, USA

Consumer advised that while driving the intake manifold cracked causing coolant to leak onto engine. Vehicle stalle oh highway.

- Oak Ridge, TN, USA

The engine intake plastic manifold cracked, which caused antifreeze to run into the engine. Dealer has been notified. Ts.

- Mitchell, SD, USA

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.

- Correctionville, IA, USA