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NHTSA — Engine And Engine Cooling: Engine Problems

1998 Pontiac Bonneville (Page 1 of 2)


definitely annoying
Crashes / Fires:
0 / 2
Injuries / Deaths:
0 / 0
Average Mileage:
40,524 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

1998 Pontiac Bonneville engine problems

engine problem

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1998 Pontiac Bonneville Owner Comments (Page 1 of 2)

problem #34

Dec 142008


  • 131,000 miles


98 Bonneville with 3800 series engine. Noticed coolant was low so I added coolant, then replaced thermostat because heater was putting out cold air. Saw big cloud of white smoke. Took to the dealer and they said that due to a known defect involving a plastic manifold and egr valve that the coolant had mixed with the oil due to holes caused by the defect in the upper and lower manifolds. Called Pontiac directly and they said sorry about your situation but no recall. Contacted previous owner and he said the same thing happened 3 years ago and he had the same thing fixed. Long story short, I'm spending $1400 for a problem that the engineers of this engine knew was a problem from the beginning of production.

- Copperas Cove, TX, USA

problem #33

Aug 102006


  • Automatic transmission
  • 84,000 miles
: the contact stated while the vehicle was stopped at an idle, the engine rpms elevated, and the oil gauge indicated low pressure, followed by engine hesitation. The vehicle was inspected by a dealer who determined no oil leak was present, but a plug wire to the engine cylinder needed to be replaced. The problem persisted after the repairs were performed. The manufacturer was contacted.

- Lewiston, ME, USA

problem #32

Nov 072005

Bonneville 6-cyl

  • Automatic transmission
  • miles
The check engine light came on and my engine locked up and radiator fluid was coming out of the head gaskets on the engine with no prior warning. This is the second time within 4 years that this has happened with this car.

- Pensacola, FL, USA

problem #31

Jul 182005

Bonneville 6-cyl

  • Automatic transmission
  • 47,000 miles


Contact states the intake manifold was leaking into cylinders, causing engine to lock, damaging starter and spark plugs. Removed and replaced for the second time on 6-17-05 at a cost of $900: The upper intake manifold and gasket, replaced spark plugs due to a recall #04V09000 fuel system/ gasoline delivery. She was refunded money by Pontiac. Now she was requesting money back fot the second time. Also, received an investigation# peo2050; concerning engine, but she has not received a recall letter.

- Laredo, TX, USA

problem #30

Apr 152003

Bonneville 6-cyl

  • Automatic transmission
  • 71,725 miles
Recall campaign: The vehicle's engine failed prior to recall notification. The consumer request reimbursement for the repair made prior to recall notification.

- Haltom City, TX, USA

problem #29

Nov 302004

Bonneville 6-cyl

  • Automatic transmission
  • 63,571 miles
While driving at any speed vehicle was running rough. It was taken to a repair shop, and mechanic determined that the problem was a crack in the intake manifold. Consumer was concerned that this was the second intake manifold replaced within two years. The manufacturer was also notified.

- Munroe Falls, OH, USA

problem #28

May 112004


  • Automatic transmission
  • 49,000 miles


While driving vehicle stalled and turned off. Vehicle was towed to dealer, who replaced the engine.

- Louisville, KY, USA

problem #27

Jul 202004

Bonneville 6-cyl

  • Automatic transmission
  • miles
While the vehicle was parked consumer noticed fluid leaking from underneath the vehicle. Consumer drove the vehicle to dealer for inspection, and mechanic determined that engine head gasket was cracked and needed to be replaced.

- Lansing, MI, USA

problem #26

Jul 292002

Bonneville 6-cyl

  • Automatic transmission
  • 80,000 miles
Intake manifold failure.

- Pocatello, ID, USA

problem #25

Jun 012004

Bonneville 6-cyl

  • Automatic transmission
  • 81,062 miles
While exiting the freeway, the engine gasket blew out. The starter had gone out as well. GM stated that nothing was wrong with the vehicle.

- Hastings, MN, USA

problem #24

Apr 202004

(reported on)

Bonneville 6-cyl

  • Automatic transmission
  • 28,000 miles


While driving engine was leaking coolant onto the intake manifold. This could result in engine failure. Consumer was informed by her friend that her vehicle was on a list of potential engine failures from coolant leaking by General Motors (GM). Consumer went to a GM dealer as soon as she learned the news, and showed extensive damage on the intake manifold which was replaced.

- La Grande, OR, USA

problem #23

Nov 082002

Bonneville 6-cyl

  • Automatic transmission
  • 60,000 miles
Plastic intake manifold failure engine locked up as driving the vehicle. Nobody injured, but definitely a safety issue. 1998 Pontiac Bonneville 2hx52K9W4202853.

- Walhallla, SC, USA

problem #22

Sep 292003


  • miles
While driving vehicle overheated and blew out. Technician diagnosed plastic intake manifold cracked. Dealer notified.

- Atlanta, GA, USA

problem #21

Sep 092003

(reported on)


  • 74,000 miles
Upper intake manifold developed cracks and anti freeze leaked onto the engine. This resulted in the motor locking up.

- Carbon, IN, USA

problem #20

Jul 192003

Bonneville 6-cyl

  • Automatic transmission
  • miles
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.

- Ashtabula, OH, USA

problem #19

Jul 022003

Bonneville 6-cyl

  • Automatic transmission
  • 88,957 miles
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

problem #18

Jun 252003

Bonneville 6-cyl

  • Automatic transmission
  • miles
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.

- Ionia, MI, USA

problem #17

Jun 242003


  • miles
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.

- Norfolk, VA, USA

problem #16

Jan 242003

Bonneville 6-cyl

  • Automatic transmission
  • miles
Consumer tried to start up vehicle, an under hood fire occurred. 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.

- Roopville, GA, USA

problem #15

Dec 152002


  • 76,000 miles
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.

- Niles, MI, USA

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