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.
2003 Mercury Grand Marquis: sudden unintended acceleration
12 of the 362 complaints about the 2003 Mercury Grand Marquis describe sudden unintended acceleration.
- owner complaints
- 12
- of this car's complaints
- 3%
- typical mileage
- 44,500
- recalls
- 0
Is there a fix? 1 service bulletin covers this area of the car. See below
Sudden unintended acceleration by model year
What owners say
Tl* the contact owns a 2003 mercury grand marquis. The contact stated that while stopped, the engine rpms increased excessively as the vehicle violently accelerated without warning. The contact crashed into another vehicle. There were no injuries and a police report was filed of the incident. The vehicle was taken to a dealer where the failure was unable to be duplicated or diagnosed. The manufacturer was notified of the failure. The vehicle was not repaired. The approximate failure and current mileage was 147,696.
Tl* the contact owns a 2003 mercury grand marquis. The contact started the ignition with the brake pedal depressed and suddenly the vehicle unintendedly accelerated when the gear lever was shifted into drive. The brake pedal was engaged numerous times and the vehicle failed to slow down and crashed into the nearby garage and also crashed into a parked vehicle. A police report was filed of the incident. The driver sustained injury to the left knee. The vehicle was completely destroyed and towed to an authorized dealer. The manufacturer was not notified of the unintended acceleration malfunction. The approximate failure mileage was 100,000. The VIN was unavailable.
Tl* the contact owns a 2003 mercury grand marquis. The contact stated that sudden acceleration was experienced in the vehicle. The vehicle began gradually lunging forward sporadically until it became harder for the contact to stop the vehicle when the failure occurred. The contact stated that once pressure was release from the accelerator pedal, the vehicle rapidly accelerated at full force. The vehicle was not inspected for the failure. The failure and current mileage was 162,000.
Tl* the contact owns a 2003 mercury grand marquis. While traveling at 4 MPH, the contact applied the brakes and the vehicle independently accelerated. The contact crashed into another vehicle as a result. There were no injuries. On a later date, while parking in a residential garage, the contact depressed the brakes and the vehicle abnormally accelerated. The vehicle crashed into the garage wall and through the master bathroom of the home. The contact sustained injuries to her pelvis from attempting to apply extreme force to the brake. A police report was available. The vehicle was not diagnosed for the unintended acceleration failure. The failure mileage was 50,000 and the current mileage was 90,000.
Sudden acceleration in a 2003 mercury grand marquis. This happened after putting the vehicle in drive, it took off at an excessive rate of speed crossed a street and jumped two curbs about 15 inches high within 5 or 6 seconds. My thoughts were "what is happening?" & "brake or you are going to die" thank god this vehicle drown in hurricane katrina. I called your ofc in 2004 after this happened and was sent a form to fill out and return to you which I never did. However, with the toyota recall it disturbs me that my ford did the same thing. An investigation needs to be made as to why these things are happening because in my case it was not a floor mat and neither was it driver's error. It is important to myself that this incident is reported and hopefully someone will take it serious and find out what the real problem is before more lives are lost. I consider myself very lucky that I was not injured and others were not injured. My vehicle sustained $5,000.00 worth of damage and at the time the incident was reported to the ford dealership. They supposedly checked the car but could find no reason for the sudden acceleration.
Tl* the contact owns a 2003 mercury grand marquis. While approaching a stop light the vehicle accelerated without intention through an intersection. After repeated brake application the vehicle would not stop. She was able to decelerate by driving onto the side of the road. She was in the process of towing the vehicle to the dealer. The failure mileage was 25,000.
Tl*the contact owns a 2003 mercury grand marquis. While waiting to make a right turn with the brake pedal depressed, the vehicle slowly began to move. The contact depressed the brake pedal harder and the engine immediately began to race. The tires began to screech and the vehicle lunged forward uncontrollably into oncoming traffic. He shifted into neutral to turn off the ignition and was five feet into the other lane. No crash occurred. The failure has occurred on four occasions. The contact restarted the vehicle and drove ten miles to his residence. He will have the vehicle towed to the dealer. The failure mileage was 44,500.
Consumer complained about sudden acceleration. Consumer was in a parking lot and put the vehicle in drive. Did not press the accelerator, and vehicle jumped the curb and flattened two tires.consumer had the vehicle towed to a body shop.
Rental auto was parked face out in hotel parking lot. Driver started auto, driver and passenger put on seat belts; with foot on brake, driver shifted into drive and car suddenly accelerated a a high rate of speed (tires smoking) across parking lot driveway and crashed into two parked cars in opposite parking spaces. Both parked cars were driven back approximately 10 to 15 feet, one of the autos went through hedges and crashed into a car parked at the street. Driver was unable to stop car, and finally turned off ignition after collision. Witness to police report stated that heard tires screeching and tires were still smoking after autos collided. Car was towed to hertz lot. Have not gotten report of cause from hertz. The entire event from placing the car in drive until it struck the parked cars took about 2 seconds (the auto travelled approximately 30 feet to impact).
Vehicle suddenly zoomed forward while leaving a parking lot. *ph on several occasions, the consumer experienced sudden acceleration with the vehicle. The dealership checked all the linkages and pedal assembly but was unable to diagnose the defect which caused this dangerous condition. *tt
While waiting for red the light to change, the vehicle suddenly accelerated. The driver could not maintain control, the vehicle jumped the curb and crashed into a ditch. *ak there was no diagnostic test performed on the vehicle. The air bag did not deploy, the electronic fuel shut off and did not engage and the seat belts did not tighten. The consumer was told that the adjustable pedals caused the accident and have caused a lot of accidents. Ford claimed that fault is the driver's fault due to their foot being on both pedals at the same time. *scc
Service bulletins that may apply
Related recalls
No recalls on record for this model year.
Questions about the 2003 Mercury Grand Marquis sudden acceleration
Is sudden unintended acceleration a common problem on the 2003 Mercury Grand Marquis?
12 of 362 owner complaints about the 2003 Mercury Grand Marquis (3%) mention sudden unintended acceleration. The model year with the most reports is 2006.
Is there a recall or service bulletin for this on the 2003 Mercury Grand Marquis?
There are 0 recalls and 1 service bulletin for the same area of the car. Check them below with your VIN.
Other symptoms on the 2003 Mercury Grand Marquis
Headlights 173Stalling 12Grinding brakes 7Power steering loss 6Wipers 6
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