2002 Mercury Grand Marquis acceleration problems

Filed Jul 17, 2025 · Acceleration, Brakes · 58,000 miles · PA

The contact owns a 2002 Mercury Grand Marquis. The contact stated while driving 50 MPH at night, the cruise control mode malfunctioned, and the speed of the vehicle increased independently. The contact stated that the brake pedal was depressed several times to the floor, but the vehicle failed to stop. The contact turned off the vehicle, and the vehicle came to a stop. The vehicle was towed to the contact's residence. The contact stated that he was afraid of driving the vehicle again. The contact unregistered the vehicle and turned the license plates of the vehicle to the Department of Motor Vehicles. The vehicle was not diagnosed or repaired by an independent mechanic or dealer. Additionally, the contact stated that the check engine and the low oil pressure warning lights had illuminated two days prior to the failure. The manufacturer was made aware of the failure and a case was filed. The failure mileage was approximately 58,000.

Filed Jul 18, 2022 · Acceleration, Electrical · CA

?yrs.ago While backing out of parking space at Calaveras Lumber, after shifting into reverse, & removing my foot from the brake; the engine appeared to receive a huge burst of fuel which shot me backward like a rocket slamming my vehicle into and wedging it under the frame of a pickup truck parked in the same lot. I am glad I was parked and had my foot on the brake prior to this unit or system malfunction otherwise the injuries could easily have been fatal on the highway. I think this defect may be a contributing factor to the car dying recently while on my way to a Wedding Reception in Roseville, which left me stranded after dark for 41/2hrs and 71/2hrs. 2days later. I have not been able to start vehicle since and mechanics unable to diagnose why the engine is fuel starved when system parts tested appear to be in good working order. Something seems to be shutting off power or preventing power to the fuel pump and it is not the inertia switch, relays, fuses etc.. Components have been previously inspected by numerous others including dealer. No Recognizable Alert/Warning Prior to Incidents!

Filed Aug 10, 2013 · Acceleration · 50,000 miles · NC

Leaving work, approximately 150 feet from parking place to parking lot exit into road. When braking to stop before entering roadway, vehicle lurched forward with engine racing at a high RPM. Pushed into neutral until stopped then park with engine still racing. Turned off and sat still for a minute then restarted with no further problem. Mechanic cannot find anything wrong. Not the first time it has happened but was the worst incident with engine being uncontrollable.

Filed Mar 29, 2013 · Acceleration · 85,000 miles · MN

Tl* the contact owns a 2002 mercury grand marquis. The contact stated that while driving 65 MPH, the vehicle accelerated independently. The vehicle was taken to the dealer for inspection and they stated that the cruise control needed to be disconnected. The vehicle was repaired but the failure recurred. The manufacturer was notified but provided no assistance. The failure mileage was 85,000. ..updated 05/01/13 *bf updated 05/06/13

Filed Aug 10, 2012 · Acceleration · MI

Tl* the contact owns a 2002 mercury grand marquis. The contact stated that whenever the air conditioner or cruise control was running, the vehicle would have sudden acceleration failures. The failure also occurred when braking to a complete stop. The contact stated that the vehicle had to be shifted into neutral in order to stop the vehicle by applying the brakes. The contact took the vehicle to a mechanic, but they were unable to determine the cause of the problem. The VIN was not available. The current mileage was 50,000 and the failure mileage was not available.

Filed May 3, 2012 · Acceleration · 115,100 miles · CA · crash

Tl* the contact owns a 2002 mercury grand marquis. The contact was at a complete stop when the vehicle accelerated abnormally. The vehicle crashed into a water heater in the contact's garage. The contact did not sustain any injuries but there were major damages to the front end of the vehicle. The manufacturer was not made aware of the failure and the vehicle was not repaired. The failure and the current mileage was 115,100.

Filed Nov 10, 2010 · Acceleration · 155,000 miles · FL

2002 mercury grand marquis lunges forward (increase RPM @1000, and loud growl from engine compartment) when I let off the accelerator, I.e. Approaching a stop light. Once I release the brake and accelerate again, all goes back to normal. There is no "check engine" light, and no other notable problems. It is intermittent and annoying.

Filed May 22, 2009 · Acceleration · 47,000 miles · FL

I have a 2002 mercury grand marquis. While stopped at a light the vehicle has all of a sudden accelerated at high speed uncontrollably. My husband had both feet on the brakes and shifted the car into neutral as the rear tires spun wildly with black smoke rolling off of them. This was terrifying. We took the car to the dealership after contacting ford and they couldn't find anything wrong so they disengaged the cruise control thinking that may be the problem. The car continues to do this and you never know when it will happen. It can be one month or four months later that this happens. We can't afford to get rid of the car but we are afraid of it. There should be some kind of recourse or allowance for us to get rid of this vehicle. Please help us!

Filed Dec 28, 2005 · Acceleration, Electrical · 24,998 miles · IA

Dt*: the contact stated the vehicle did not always start. When it did start the engine stalled while idling. To alleviate stalling the accelerator pedal must be pumped hard while starting the vehicle. The vehicle has been to the dealership multiple times and they were unable to duplicate the problem. The iac valve was replaced, and the computer was reprogrammed. Neither of these efforts repaired the problem.

Filed Apr 28, 2004 · Acceleration · 40,000 miles · FL

While driving vehicle off of carwash conveyor, the engine raced to full speed. I had to us both feet on the brake, and shift into neutral to stop the car. With the front tires locked, the car still accellerated over two speed bumps before stopping.