1991 Pontiac Bonneville: common problems

Owners of the 1991 Pontiac Bonneville filed 22 complaints with NHTSA, most often about service brakes and engine and cooling. Details by component below, with sources.

Key figures

Owner complaints: 22
involving a crash: 3

What fails most often

1 Service brakes 27% of all complaints
2 Engine and cooling 14% of all complaints
3 Powertrain 14% of all complaints
4 Electrical system 9% of all complaints
5 Latches, locks, linkages 9% of all complaints
6 Vehicle speed control 9% of all complaints
7 Equipment 5% of all complaints
8 Fuel system 5% of all complaints

Circle size and colour show each component’s share of NHTSA complaints. Schematic only, not a drawing of the exact model.

Service brakes: 6 complaints (27% of all), 1 of them with a crash reported by the owner.
Engine and cooling: 3 complaints (14% of all).
Powertrain: 3 complaints (14% of all).
Electrical system: 2 complaints (9% of all).
Latches, locks, linkages: 2 complaints (9% of all).

Engines and transmissions

US-market versions per EPA. On the right: how many NHTSA complaints name this engine or transmission type.

3.8 L · petrol · 6 cyl
automatic, 4-speed

Drive: FWD

Symptoms owners describe

How many of the 22 NHTSA complaints mention each symptom (automatic count from complaint text; one complaint can mention several).

door locks, latches, handles2 · 9%
stalls while driving2 · 9%
brake failure1 · 5%
A/C or heater1 · 5%
rust, corrosion1 · 5%
seat belts1 · 5%
smoke, burning smell, fire1 · 5%
transmission slipping1 · 5%
vibration1 · 5%
warning lights, check engine1 · 5%

Components owners complain about

Component	Owner complaints	involving a crash
Service brakes	6	1
Engine and cooling	3	0
Powertrain	3	0
Electrical system	2	0
Latches, locks, linkages	2	0
Vehicle speed control	2	0
Equipment	1	0
Fuel system	1	0
Seat belts	1	1
Seats	1	1
Structure	1	0
Other	1	0

What owners report

Short excerpts of NHTSA complaints in the original wording. These are owner statements not verified by NHTSA; personal data removed.

While driving on freeway I was struck by a drunk driver going approx. 70-75mph. I was hit in the left rear of the car and I was immediately thrown back.after pulling over I found out that the seat back had broken and was in the fully reclined position.
Seats · crash · 1999-03-10 · NHTSA complaint #704252
Failure of the driver side seat belt, belt did not lock when the consumer was in an accident. Tt
Seat belts · crash · 1996-02-20 · NHTSA complaint #979406
Brakes failed while driving-pedal went to the floor-causing accident. Tt
Service brakes · crash · 1995-08-15 · NHTSA complaint #970444
Tl contact owns a 1991 pontiac bonneville. While driving approximately 45 mph in cold weather conditions, the transmission oil cooler line separated and caused transmission fluid to leak excessively.
Powertrain · 2008-12-03 · NHTSA complaint #10250651
This caused oil to leak onto the hot catalytic converter causing a fire to erupt within the engine compartment and spread through the air conditioning blower motor and into the cab of the vehicle. The driver exited the vehicle without injuries. The fire department was contacted and extinguished the fire.
Engine and cooling · 2006-08-15 · NHTSA complaint #10165522
Consumer stated that after market master cylinder had to be replaced on three occasions because the plunger pin kept breaking. This caused brake pedal to go to the floor when brakes were applied. Unable to get in contact with the manufacturer, fenco / fenwick automotive products.
Service brakes · 2003-09-30 · NHTSA complaint #10041965
I have changed the dash and had all wiring checked and everything is fine except that I have no dash lights could someone please tell me what the problem could be.
Electrical system · 2002-02-05 · NHTSA complaint #757637
The battery and alternator were replaced due to failure.
Electrical system · 2000-12-19 · NHTSA complaint #558113

When owners complained

NHTSA complaints by filing year. The peak shows at what age the problems show up most.

19956
19963
19973
19982
19993
20001
20021
20031
20061
20081

Comparison

By complaint count this model year ranks 7,906 of 36,659 model years in the NHTSA data (top 22% most complained about).

On average one model year of the Bonneville has 71 complaints (28 years in the data). This year has 22, below average.

What to check before buying

Service brakes. Pedal feel, ABS operation, leaks, discs and hoses.
Engine and cooling. Radiator and fan after a frontal hit, coolant level and condition, overheating.
Powertrain. Shift quality under load, harsh shifts, transmission codes, CV joints.
Electrical system. Scan all modules, test the battery and alternator, inspect connectors near the impact zone.

Questions and answers

What are the most common problems with the 1991 Pontiac Bonneville?

Owner complaints to NHTSA most often mention: service brakes, engine and cooling, powertrain. Total complaints: 22. The most frequent symptoms in complaint texts: door locks, latches, handles (9%), stalls while driving (9%), brake failure (5%).

How many service bulletins (TSB) were issued for the 1991 Pontiac Bonneville?

NHTSA lists 0 manufacturer service bulletins for this year. A bulletin tells dealers how to diagnose or fix a known issue; it is not a recall.

Should I buy a 1991 Pontiac Bonneville from a US auction?

Owner complaints describe defects, not crash damage. Before bidding, check the components listed above and review the lot photos: VinWind builds a report of visible and hidden damage by VIN.

Other 1991 models

Read also

Sources: public NHTSA data (USA): service bulletins and owner complaints; YouTube: links to videos credited to their authors. Complaints are owner statements not verified by NHTSA, and describe defects rather than crash damage. Data updated 2026-11-06.