Problems · by component
1998 Pontiac Bonneville engine and engine cooling problems
196 owner complaints to NHTSA about the 1998 Pontiac Bonneville cite engine and engine cooling, 69% of all 284 complaints for this model year.
Complaints
196
69% of all complaints
Crashes
1
Reported by owners
Fires
17
Reported by owners
Injuries
2
Reported by owners
What owners say about the engine and engine cooling
Verbatim from NHTSA complaints, newest first
“THE BACK TWO CRADLE MOUNTS ON BOTH SIDES RUSTED OUT AND MOUNTS PULLED THROUGH THE CRADLE CAUSING THE STEERING TO BECOME LOOSE FILLING AND CAUSING STEERING TO BE OUT OF ALIGNMENT AND WHEN HIT BRAKES FRONT WOULD DART ONE WAY OR THE OTHER AND LOTS OF NOISE COMING FROM UNDER VEHICLE FROM CRADLE BOUNCING WHEN HITTING BUMPS TRIED THE FIND ONE IN JUNK YARDS AND ALL ARE THAT WAY. *TR”
“TL* THE CONTACT OWNS A 1998 PONTIAC BONNEVILLE. THE CONTACT STATED THAT WHILE DRIVING APPROXIMATELY 20 MPH THE VEHICLE SUDDENLY STALLED. THE CONTACT ATTEMPTED TO RESTART THE VEHICLE, BUT IT HESITATED TO START. THE VEHICLE WAS TOWED TO AN INDEPENDENT MECHANIC, WHO STATED THAT THE PLASTIC GASKET FROM THE INTAKE MANIFOLD FAILED AND CAUSED ENGINE COOLANT TO LEAK INTO THE ENGINE. THE MANUFACTURER WAS MADE AWARE OF THE FAILURE AND ADVISED THE CONTACT TO TAKE THE VEHICLE TO AN AUTHORIZED DEALER FOR DIAGNOSTICS.THE VEHICLE WAS TOWED TO THE DEALER WHERE THE TECHNICIANS REPLACED THE INTAKE MANIFOLD AND THE INTAKE MANIFOLD GASKET. AFTER THE REPAIRS, THE CONTACT HEARD A KNOCKING NOISE COMING FROM THE ENGINE. THE VEHICLE WAS TOWED BACK TO THE DEALER FOR DIAGNOSTICS, BUT WAS NOT REPAIRED A SECOND TIME. THE APPROXIMATE FAILURE MILEAGE WAS 80,433.”
“98 PONTIAC 86,000 MILES INTAKE MANIFOLD FAILED FOR THE SECOND TIME... PARTS REPLACED...SPARK PLUGS (FOULED)..STARTER ASSEMBLY.. MOTOR WAS WATERLOCKED BROKE STARTER...INTAKE MANIFOLD GASKET REPLACED.....OIL CHANGED DUE TO COOLANT CONTAMINATION...REPLACE ANTIFREEZE...TOTAL BILL LABOR AND PARTS... $1387.99..GM HAS NUMEROUS SERVICE BULLETINS ON THIS ISSUE...WHY HAS A RECALL NOT BE ISSUED FOR THIS PROBLEM ?? *TR”
“THE AIR INTAKE GASKET HAS FAILED FOR 2 REASONS. 1 FACTORY TIGHTLY PUT THE BOLTS ON TO TIGHT. 2 PLASTIC GASKET AND PLASTIC MANIFOLD PARTS DO NOT MEET GOVERNMENT SAFETY STANDARDS FOR, FAILURE AVOIDANCE, BECAUSE OF MATERIALS USED TO CONNECT THE PLASTIC TO METTLE CREATING A DANGEROUS SITUATION. *TR”
“MY UPPER INTAKE MANIFOLD LEAKS ENGINE COOLANT INTO THE COMBUSTION CHAMBERS AND INTO THE CRANKCASE. THE EGR TUBE MELTS THE UPPER PLASTIC MANIFOLD I HAVE HAD THE UPPER AND LOWER INTAKE REPLACED FOR THIS ISSUE ONCE BEFORE WITH GM PARTS AND IT HAPPENING AGAIN. IF IT NOT FIXED THE COOLANT CAN CONTAMINATE MY OIL AND LOCK UP MY ENGINE WHEN TRAVELING DOWN THE ROAD AND POSSIBLY CAUSE ME TO CRASH. IF THE ENGINE LOCKS UP I WILL LOSE POWER STEERING AND BRAKING ABILITY. *TR”
“I OWN A 1998 PONTIAC BONNEVILLE SE. I SAW RECENTLY THAT GM WAS RECALLING 1.5 MILLION VEHICLES WITH THE 3800 3.8 LTR V6. WAS WONDERING HOW THEY COULD RECALL THOSE VEHICLES AND NOT MINE, MY CAR IS IN THE SAME YEAR RANGE "1998" AND HAS THE EXACT MOTOR "3800 3.8 V6" AND OIL DRIPS ON MANIFOLD ON MY CAR AS WELL. WHAT KIND OF INFO CAN I GET ON THIS? THANK YOU *TR”
Showing 6 of 196 reports. Read every report on NHTSA.gov.
Data from NHTSA Complaints API (owner reports, unverified) · synced Nov 10, 2026NHTSA vehicle page
Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.