Problems · NHTSA complaints

2003 Mercury Grand Marquis problems

Owners filed 395 complaints about the 2003 Mercury Grand Marquis with NHTSA between Oct 2002 and May 2026. The most-cited component is exterior lighting (215).

Complaints
395
Filed with NHTSA
Crashes
26
Reported by owners
Fires
3
Reported by owners
Injuries
18
People reported injured
Deaths
0
Reported to NHTSA
01 —By component

Complaints by component

One complaint can cite several components
  1. Exterior lighting215
  2. Electrical system55
  3. Vehicle speed control32
  4. Steering32
  5. Suspension32
  6. Engine and engine cooling15
  7. Air bags13
  8. Power train12
  9. Structure12
  10. Wheels10
  11. Visibility8
  12. Service brakes, hydraulic8
  13. Fuel system, gasoline7
  14. Engine5

Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.

Data from NHTSA Complaints API · synced Nov 9, 2026NHTSA vehicle page
02 —Trend

When complaints were filed

Does it get worse with age? Complaints per calendar year filed
View as table
Model yearComplaints filed per calendar year
20024
200335
200418
200513
20069
20079
200810
200920
201040
201123
201221
201320
201444
201526
201629
201721
201810
20199
20204
20214
20227
20237
20248
20253
20261

Mileage at failure isn’t a structured field in NHTSA complaint data, so we don’t chart it. Some owners mention it in their reports below.

03 —Owner reports

Top problems in owners’ words

Verbatim from NHTSA complaints, newest first

Exterior lighting

215 reports5 crashes1 related recall
“The contact owns a 2003 Mercury Grand Marquis. The contact that the headlights were intermittently inoperable. Additionally, the contact stated that the instrument panel lights, the brake lights, and the turn signal lights were inoperable. The contact who is a mechanic, had inspected the fuses, the fuse box, and other unknown parts, but found no failures. The dealer was notified of the failure. The vehicle was not diagnosed or repaired. The contact related the failure to NHTSA Campaign Number: 15V861000 (Exterior Lighting); however, the VIN was not included. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was approximately 160,000.”
Owner complaint to NHTSAFiled May 13, 2025Exterior lighting, Electrical systemODI 11660627

Electrical system

55 reports4 crashes2 fires
“The contact owns a 2003 Mercury Grand Marquis. The contact stated that the headlights and taillights were inoperable, and the trunk failed to open. Additionally, all the doors failed to manually lock, and while utilizing the key fob, the door locks were inoperable. The door-ajar message was displayed. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline. The contact stated that the failure was related to NHTSA Campaign Number: 15V861000 (Exterior Lighting). The approximate failure mileage was 179,000. The VIN was not available.”
Owner complaint to NHTSAFiled Mar 8, 2024Electrical system, Exterior lighting, Latches/locks/linkagesODI 11576191

Vehicle speed control

32 reports14 crashes
“I started Mercury with foot on break like normal. Shifted into reverse. Car accelerated backwards at full speed. Brakes did not stop car. Attempted to shift into neutral but went into drive instead. Car accelerated forward at full speed with my foot still on break. Car hit metal post and tree knocking them down and dragging the tree 50 to 60 feet before stopping with my foot still on the break. Car had stopped accelerating. I turned off the ignition. This unintended acceleration had happened before. Two different dealers attempted to fix the problem. Both of them thought they had been successful but it happened again. Previously, applying the brakes stopped the car, but not this time. Someone could have been injured severely or killed.”
Owner complaint to NHTSAFiled Jan 20, 2023Electrical system, Vehicle speed control, EngineCrash reportedODI 11502872

Steering

32 reports
“I am the owner of a 2003 Mercury Grand Marquis. Several weeks ago the power steering on the vehicle quit. This was not the result of the power steering pump. The linkage in the steering system had ceased, causing the vehicle to be dangerously unsteerable. I have had this repaired at a cost of $575 dollars. I believe this is a safety issue that need immediate investigation and a safety recall. I contacted Ford Motor Company and was sent to Chat contact Shakura who gave me the Corporate runaround. We were lucky as this happened on a side road at low speed. If it had happened on an Interstate with speeds of 65 to 80 MPH I feel this could have resulted in a major accident. I should also point out this steering item is in Ford Crown Victorias and more than likely in Lincoln Continentals. Please advise and contact me with questions. Thank you in advance as this need to be resolved.”
Owner complaint to NHTSAFiled Feb 2, 2022SteeringODI 11450023

Suspension

32 reports1 fire
“Almost had accidents because lights failed, headlights and taillights failed at night, including dash lights today, creating safety hazard. Seat tilt failed, and body mount frame bushing failed. Mirror tilt switch failed. Fuel filler neck leaks when filled. Very scary especially at night. Please recall and fix before we get hurt.”
Owner complaint to NHTSAFiled Nov 23, 2022Suspension, Exterior lighting, Unknown or otherODI 11494762

Engine and engine cooling

15 reports1 crash
“THE PLASTIC INTAKE MANIFOLD OF MY 2003 MERCURY 4.6L V-8 CAME APART AND LET THE COOLANT LEAK OUT ONTO THE ENGINE.THIS CAR WAS BUILT IN CANADA IN MID-2002 THE PROBLEM IS RAMPANT IN MANY YEARS OF THE FORD CO CARS. AND IN 2001 A CLASS ACTION SUIT WAS FILED, IN WHICH FORD WAS DIRECTED TO PAY DAMAGES TO ALL OWNERS (1,800,000 OWNERS) OF THIS TYPE OF ENGINE AND FORD WAS SUPPOSED TO STOP INSTALLING THAT ITEM AS OF THEN. CLEARLY THEY DID NOT STOP AND THAT FAILURE COST ME OVER $1000.00 TO REPAIR. THE REPAIR PART IS NOW PARTLY ALUMINUM AND PART PLASTIC. SEE: HTTP://WWW.CONSUMERAFFAIRS.COM/NEWS04/2005/FORD_MANIFOLD_SUIT.HTML. *TR”
Owner complaint to NHTSAFiled Feb 5, 2010Engine and engine coolingODI 10306527
Data from NHTSA Complaints API (owner reports, unverified) · synced Nov 9, 2026

Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.