"How reliable is the 1999 Pontiac Bonneville?"

"Based on 176 NHTSA complaints, the 1999 Pontiac Bonneville has a median complaint mileage of 70096 miles. The most common issue is ENGINE AND ENGINE COOLING:ENGINE:GASOLINE."

"What are common problems with the 1999 Pontiac Bonneville?"

"The most frequently reported component in NHTSA complaints for the 1999 Pontiac Bonneville is ENGINE AND ENGINE COOLING:ENGINE:GASOLINE, accounting for a significant portion of the 176 total complaints filed."

1999 Pontiac Bonneville: Reliability Data

Source: NHTSA — 176 complaints

176

Total Complaints

70,096mi

Median Mileage

ENGINE AND ENGINE COOLING:ENGINE:GASOLINE

Top Issue

Crash Reports

When Do Complaints Happen?

Distribution of NHTSA complaints by vehicle mileage at time of report.

50,000 25th Percentile

70,096 Median Mileage

102,000 75th Percentile

What Fails?

Most reported component issues from NHTSA complaints.

ENGINE AND ENGINE COOLING:ENGINE:GASOLINE

ENGINE AND ENGINE COOLING:ENGINE

ENGINE AND ENGINE COOLING

ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:MANIFOLD/HEADER/MUFFLER/TAIL PIPE

FUEL SYSTEM, GASOLINE

ENGINE AND ENGINE COOLING:COOLING SYSTEM

ELECTRICAL SYSTEM:IGNITION

POWER TRAIN:AUTOMATIC TRANSMISSION

FUEL SYSTEM, GASOLINE:DELIVERY

AIR BAGS:FRONTAL

Severity Assessment

Crashes

Fires

Injuries

Deaths

Sample Complaint Reports

"VEHICLE WAS PARKED WHEN CONSUMER STUCK KEY INTO IGNITION AND THE DRIVER'S SIDE AIR BAG DEPLOYED. VEHICLE IS A RENTAL BY AVIS 412-472-5200. CONSUMER DOES NOT KNOW IF AIR BAG WAS REPAIRED. *AK *ML"

"FALSE DEPLOYMENT OF AIR BAG DURING START UP CAUSED INJURY TO DRIVER."

"ENGINE STALLED WITHOUT WARNING WHILE COASTING OR STARTING OFF FROM STOP - 3 TIMES. DEALER HAD A COMPUTER PROGRAM UPGRADE WHICH HE INSTALLED AFTER THE FIRST TWO FAILURES. VEHICLE IS CURRENTLY AT DEALER - WHO, AS OF THIS AFTERNOON, HAS NOT BEEN ABLE TO REPRODUCE THE FAILURE."

Source: NHTSA ODI Complaints Database. Names and identifying details omitted.

Data source: View this vehicle on NHTSA.gov | NHTSA ODI Complaints Database. Public domain.

Methodology: Complaint counts and mileage distributions are computed directly from consumer-reported NHTSA complaints. This data represents reported issues, not failure rates — vehicles without complaints are not represented. Full methodology.

Data through: 2026-03-28