Total Complaints
24 filings
MERCURY GRAND MARQUIS · model year
24 NHTSA complaints, 2 crash reports. A VIN lookup is required to determine whether a specific vehicle has an unrepaired recall.
NHTSA overall rating
Not crash-tested
New Car Assessment Program
The 1984MERCURYGRAND MARQUIS carries 24 consumer safety complaints in NHTSA's Office of Defects Investigation database for this specific model-year cohort. Within that volume, owners reported 2 crashes, 6 fires, 1 injury, and 2 fatalities. No NCAP 5-star crash-test rating is available for this model year in the federal database.
The most frequently selected component label in reports for the 1984 GRAND MARQUIS is structure:body with 3 filings, followed by electrical system:ignition:switch (3) and electrical system:wiring:front underhood (3). Complaint categories reflect owner reports and intake categorization; they do not establish a defect pattern or cause.
NHTSA currently has 3 investigation files overlapping the 1984 GRAND MARQUIS. Owners comparing this cohort against neighboring years should read the complaint-by-year trend as report volume, not a causal diagnosis. Use the related-complaint feed and the official recall lookup when researching a specific vehicle.
Total Complaints
24 filings
Crashes Reported
2 reports
Source
NHTSA ODI
Federal complaints database
At or below the fleet median complaint volume.
| Component | Count |
|---|---|
| STRUCTURE:BODY | 3 |
| ELECTRICAL SYSTEM:IGNITION:SWITCH | 3 |
| ELECTRICAL SYSTEM:WIRING:FRONT UNDERHOOD | 3 |
| VEHICLE SPEED CONTROL | 3 |
| ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:GAS RECIRCULATION VALVE (EGR VALVE) | 2 |
| UNKNOWN OR OTHER | 2 |
| ENGINE AND ENGINE COOLING:ENGINE:GASOLINE | 2 |
| VEHICLE SPEED CONTROL:ACCELERATOR PEDAL | 1 |
| FUEL SYSTEM, GASOLINE:STORAGE:TANK ASSEMBLY | 1 |
| ENGINE AND ENGINE COOLING:EXHAUST SYSTEM | 1 |
| ELECTRICAL SYSTEM:IGNITION | 1 |
| SUSPENSION:REAR | 1 |
| FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM | 1 |
ENGINE WILL IDLE VERY HIGH AT STOPS AND WILL STALL WHEN TURNING. *SLC
VEHICLE EXPERIENCES SUDDEN ACCELERATION WITHOUT WARNING, THE DEALER HAS BEEN UNSUCCESSFUL IN FINDING A REMEDY FOR THE PROBLEM. *SLC
NO SUMMARY
THE CAR CONSTANTLY STALLS UPON TURNING, DECELERATION, AND BRAKING, CAUSING NEAR TRAFFIC ACCIDENTS. CAR WAS CHECK OVER FOR MALFUNCTION, BUT TO NO AVAIL.THE REAR OF THE CAR IS SAGGING VERY BADLY, CAUSING ME TO HAVE TO REPLACE THE REAR BUMPER AND TAILPIPE. THE HEIGHT OF THE CAR FROM GROUND TO FRAME IS APPROX. 6 3/4 INCHES. THE CAR CONSTANTLY BOTTOMS OUT IN THE REAR EVEN WITHOUT A LOAD, SPRINGS HAVE BEEN REPLACED 4 TIMES AND THE CAR SAGS AFTER 3 MONTHS OR SOONER.
THE CAR CONSTANTLY STALLS UPON TURNING, DECELERATION, AND BRAKING, CAUSING NEAR TRAFFIC ACCIDENTS. CAR WAS CHECK OVER FOR MALFUNCTION, BUT TO NO AVAIL.THE REAR OF THE CAR IS SAGGING VERY BADLY, CAUSING ME TO HAVE TO REPLACE THE REAR BUMPER AND TAILPIPE. THE HEIGHT OF THE CAR FROM GROUND TO FRAME IS APPROX. 6 3/4 INCHES. THE CAR CONSTANTLY BOTTOMS OUT IN THE REAR EVEN WITHOUT A LOAD, SPRINGS HAVE BEEN REPLACED 4 TIMES AND THE CAR SAGS AFTER 3 MONTHS OR SOONER.
CONSUMER HAD THE VEHICLE IN PARK, THEN PUT THE VEHICLE IN DRIVE, AND THE VEHICLE JUST TOOK OFF, CAUSING THE CONSUMER TO RUN IN A YARD AND WENT DOWN AN ENBANKMENT AND HIT A TREE. THE INSURANCE COMPANY CLAIM THAT THE THROTTLE GOT STUCK. *AK *ML
WHEN COMING TO A STOP THE BRAKE PEDAL AND THE ACCELERATOR HAVE TO BE DEPRESSED TO KEEP THE VEHICLE FROM STALLING. *AK
WHILE DRIVING VEHICLE ON WET SLUSHY TYPE PAVEMENT OWNER TOOK FOOT OF ACCELERATOR AND ENGINE CONTINUED TO REV. CAUSE HAS NOT BEEN DETERMINED. *AK
ENGINE FAILED TO START AFTER VEHICLE PARKED OVERNIGHT, CAUSE UNKNOWN, NOT CHECKED BY DEALER, SEARS CHECKED BATTERY/ALTERNATOR, NO PROBLEM. VEHICLE AVAILABLE FOR INSPECTION. *AK
EVP SENSOR CORE SYSTEM FAILED, KEEPING EGR VALVE OPEN, CAUSING ENGINE TO STALL. (FIRST VEHICLE ON 601573)
HEAD LINER FABRIC/SUN VISORS HANGING DOWN, OBSCURING VISION.
DASHBOARD VINYL CRACKED, DETERIORATED AND DISINTEGRATED, FALLING INTO SPEAKER OPENINGS, CREATING POTENTIAL FOR ELECTRICAL SHORT.
DROVE 5 MILES, SHUT OFF ENGINE, RETURNED WITHIN 5 TO 6 MINUTES, FLAMES WERE COMING UP FROM UNDERHOOD IN AREA OF WINDSHIELD, FUEL INJECTED ENGINE. *AK
VEHICLE EXPLODED INTO FLAMES WHEN HIT FROM BEHIND. *DH
AFTER STARTING AUTO TO WARM IT UP THEN WALKED AWAY AND SUDDENLY IT BLEW UP AND BURNED EVERYTHING UNDER THE HOOD AND DASH. *AK
AFTER STARTING AUTO TO WARM IT UP THEN WALKED AWAY AND SUDDENLY IT BLEW UP AND BURNED EVERYTHING UNDER THE HOOD AND DASH. *AK
PARKED VEHICLE, SMOKE STARTED TO COME FROM UNDERNEATH THE HOOD. RESULTING IN VEHICLE FIRE BY FIREWALL NEAR THE MOTOR. *AK
PARKED VEHICLE, SMOKE STARTED TO COME FROM UNDERNEATH THE HOOD. RESULTING IN VEHICLE FIRE BY FIREWALL NEAR THE MOTOR. *AK
HEAD LINER IS LOOSE, BLOCKING VISIBILITY.
IGNITION SWITCH FAILS.
Data vintage: August 2026. Sources: NHTSA Office of Defects Investigation (ODI) complaints database, NHTSA recall campaign API, NHTSA NCAP crash-test ratings, and NHTSA FARS for fatality cross-reference.
Every figure on PlainCars is rendered directly from NHTSA complaint and safety data, no number is typed in by an editor. This year-specific record is rendered from NHTSA ODI, recall, and NCAP rows for the 1984 MERCURY GRAND MARQUIS; no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of August 2026.
Read our methodology - how this data is sourced, computed, and verified.