Huge win for car owners! All TSBs to be made public. The Center for Auto Safety just made the NHTSA (US Government) make public the full text of all TSBs from now on. They are the same organization that has petitioned the NHTSA & filed lawsuits to protect car owners over exploding gas tanks & other major safety issues. Whenever you drive in your car, you are safer thanks in part to a lot of work over the years by this small but very effective consumer advocacy group.

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really awful
Crashes / Fires:
1 / 0
Injuries / Deaths:
5 / 0
Average Mileage:
14,167 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2003 Mercury Grand Marquis engine problems

engine problem

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2003 Mercury Grand Marquis Owner Comments

problem #7

Jun 092007

Grand Marquis 8-cyl

  • Automatic transmission
  • 36,000 miles


The contact owns a 2003 Mercury Grand Marquis. While driving 10 mph, the engine began to rev and the brakes failed. The contact stated that it sounded as if the transmission snapped. The dealer stated that nothing was wrong with the vehicle, however recalls were issued for that model of vehicle. The vehicle has been at the dealer for two weeks. The powertrain was unknown. The current and failure mileages were 36,000.

- Louisville, KY, USA

problem #6

Feb 182007

Grand Marquis 8-cyl

  • Automatic transmission
  • 36,200 miles
- the contact stated that while driving his 2003 Mercury Grand Marquis (36200 failure mileage) and attempting to stop at a red light, with his foot on the brake, the vehicle accelerated and got away from the contact for about one yard. The contact had to forcefully apply the brake again, but nothing happened. While the vehicle was still accelerating, the contact had to put the vehicle in neutral and turn the power off. The vehicle was taken to a dealer, who discovered that a defective 2W7Z-9F715-ba valve 226 had to be replaced. The current mileage was 36,780 miles.

- Medford, MA, USA

problem #5

Dec 292002

Grand Marquis 8-cyl

  • 39 miles
Nar 02/28/2003 mr consumer experinced problems with engine since delivery of the vehicle.

- San Antonio, TX, USA

problem #4

Mar 312003

Grand Marquis 8-cyl

  • Automatic transmission
  • 26,890 miles


2003 Mercury grand marques stalls at or near idle speed. Has stalled when backing up, when starting forward from stop at traffic light. Have had it into the dealer, ray pearman Lincoln Mercury 4 time for a total of 9 days. They have been unable to fix problem as of yet. The dealer confirmed that there was a stalling problem. They have replaced the idle air control valve and the mass air flow sensor. Each time they thought they had it fixed and had me take the car, it has stalled again. One time it stalled as I was backing out of the dealer service department. It is currently at the dealer and they are trying to find the problem.

- Huntsville, AL, USA

problem #3

Jan 112003

Grand Marquis 8-cyl

  • Automatic transmission
  • miles
While waiting in line for gas with foot on brake, engine started to race. Engine continued to race when car was put in neutral and then park. Turned engine off and restarted, racing did not reoccur after restarting.

- Frederick, MD, USA

problem #2

Jun 282003

Grand Marquis 8-cyl

  • Automatic transmission
  • miles
After starting and shifting into drive the engine raced and there was unexpected acceleration and the car would not stop even while applying brake. Turned vehicle off after crash and the engine continued to sound like it was running.

- Rehoboth Beach, DE, USA

problem #1

Dec 242003

Grand Marquis 8-cyl

  • Automatic transmission
  • 39 miles
There was a severe vibration in the engine, when the vehicle idled. There was a general chassis vibration at speeds of 38 which was attributed to out of rounds tires.

- San Antonio, TX, USA

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