Reliability, what owners report, and what it costs to keep.
AVOIR's read: running costs are the problem rather than the car itself.
Owners have filed 90 complaints with NHTSA about the 1991 Mercury Grand Marquis, and it carries 2 recalls. These are owner allegations rather than confirmed defects, but the pattern of what people complain about is the most useful signal a used buyer has.
| Area | Complaints | Share |
|---|---|---|
| Electrical system | 21 | 23% |
| Vehicle speed control | 12 | 13% |
| Air bags | 11 | 12% |
| Engine and engine cooling | 7 | 8% |
| Power train | 7 | 8% |
| Service brakes | 7 | 8% |
| Fuel system | 4 | 4% |
| Structure | 3 | 3% |
| Exterior lighting | 3 | 3% |
| Parking brake | 2 | 2% |
Verbatim from NHTSA complaint records, trimmed for length.
1991 MERCURY GRAND MARQUIS. CONSUMER WRITES IN REGARDS TO DEFECTIVE AFTER MARKET ELECTRICAL COMPONENT. *LD THE CONSUMER PURCHASED A NEW STARTER SOLENOID RELAY, BWD SELECT BRAND BY STANDARD MOTOR PRODUCTS INC., AFTER A
NHTSA complaint: Electrical system
ALTERNATOR SPONTANEOUSLY CAUGHT ON FIRE AFTER THE CAR WAS STOPPED AND TURNED OFF. *JB
NHTSA complaint: Electrical system
POWER WINDOW ON THE PASSENGER SIDE DOES NOT GO DOWN AT ALL.THE CAR KEEPS KILLING THE BATTERY AND I'VE ALREADY SPENT MONEY ON AN ALTERNATOR USED. BRAKE PEDAL SEEMS STIFF AT TIMES AND DOES NOT GRAB WELL AT TIMES. AIR BAG L
NHTSA complaint: Service brakes
AFTER PARKING VEHICLE IN DRIVEWAY CONSUMER WAS EMPTYING THE TRUNK AND NOTICED SMOKE COMING FROM UNDER THE HOOD. A FIRE SOON ERUPTED FROM THE PASSENGER'S SIDE UNDER THE HOOD, AND WAS QUICKLY EXTINGUISHED. AFTER CAREFUL
NHTSA complaint: Electrical system
V8 CYLINDER ENGINE IS RUNNING 70. 8 CYLINDER IS NOT GETTING OIL, THIS CAUSES VEHICLE TO STALL OUT. PLEASE PROVIDE ANY FURTHER INFORMATION.*AK
NHTSA complaint: Engine and engine cooling
CONSUMER WAS BACKING OUT OF DRIVEWAY AND DRIVER'S SIDE AIRBAG WENT OFF WITHOUT PRIOR WARNING. BE ADVISED SHE DIDN'T STRIKE ANY OBJECTS/ A CURB OR TREE. CONSUMER SUSTAINED BURNS TO HER BODY.*AK
NHTSA complaint: Air bags
VEHICLE STARTS AND RIDES FOR ABOUT 20 MILES, THEN IF I HAVE TO STOP FOR SOME REASON THE CAR STALLS ESPECIALLY IF I HAVE TO BACK UP. THIS HAPPENS ALMOST DAILLY. NO ACCIDENTS YET BUT I AM AFRAID I WILL CAUSE A SERIOUS AC
NHTSA complaint: Engine and engine cooling
FORD MOTOR CO. SAID THEY ARE WAITING FOR A JUDGE DECISOIN ON A PROGRAM TO REPLACE. THEY SHOULD JUST RECALL AFFECTED VEHICILES. NO SAFETY DEFECT LISTED. *AK
NHTSA complaint: Electrical system
NHTSA lists 2 recall campaigns for the 1991 Mercury Grand Marquis. Recalls are free to have fixed at a franchised dealer regardless of who owns the car now, but only if they were never done, so check the VIN of the specific car rather than trusting the model.
THE PARK ROD ASSEMBLY CONTAINS A PARK CAM WITH INADEQUATE SURFACE HARDNESS, WHICH COULD LEAD TO PARK DISENGAGEMENT OR NO PARK ENGAGEMENT WHEN THE LEVER IS PLACED IN PARK.
Risk: IF PARK IS NOT ENGAGED AND THE PARKING BRAKE IS OFF, AVEHICLE ROLL-AWAY COULD RESULT.
Fix: REPLACE PARK ROD ASSEMBLY ON AUTOMATIC TRANSMISSIONS.
THREADED INFLATOR COMPONENTS MAY HAVE BEEN DAMAGED DURING ASSEMBLY WHICH MAY ALLOW COMPONENTS TO SEPARATE WHEN INFLATOR RECEIVES A SIGNAL TO DEPLOY THE AIR BAG.
Risk: INFLATOR COMPONENT SEPARATION ALLOWS HOT COMBUSTION GASES TO ESCAPE INTO THE PASSENGER COMPARTMENT WHICH COULD RESULT IN INJURIES TO VEHICLE OCCUPANTS.
Fix: REPLACE AIR BAG MODULES CONTAINING POTENTIALLY DEFECTIVE INFLATORS.
| Reliability raw | 83 | excellent |
|---|---|---|
| Longevity est. | 78 | good |
| Maintenance | 59 | average |
| Depreciation | 60 | average |
| Performance | 71 | good |
| Efficiency | 35 | below average |
Percentile ranks against other midsize & large cars in the catalog.
What stands behind each score for this car:
Owners have filed 90 complaints with NHTSA for this model-year, and electrical system is the most reported area with 21 of them (23%). There are 2 recalls on record. Check any specific car against its VIN before buying.
AVOIR scores its reliability 83/100 (excellent) from NHTSA recall campaigns and complaint density. That figure is a raw complaint count, not yet adjusted for sales volume, so a high-volume model scores worse than it deserves.
AVOIR scores its longevity 78/100, but that figure is an estimate built from the powertrain and the brand's record, not a measurement. A 1991 car has no 200,000-mile population to observe yet, so treat it as a prior rather than evidence.
AVOIR's read: skip unless cheap, because running costs are the problem rather than the car itself. Its overall ownership score is 68/100. Condition, mileage and service history still matter more than any score, so get a pre-purchase inspection on the specific car.
Sources: NHTSA recalls and complaints, EPA fuel economy, IIHS awards, and live market listings. A score describes a model-year, not the individual car in front of you. Get a pre-purchase inspection.