2008 Mercury Grand Marquis acceleration problems

Filed Mar 9, 2021 · Acceleration · 78,013 miles · IL

I was driving in town and several times when I slowed down to stop at a stop sign or corner, after braking my car accelerated by itself. The engine revved up and made the car jump forward. I had to slightly release the brake snd brake harder to stop and avoid going into the intersection.

Filed May 11, 2019 · Acceleration, Transmission · 88,500 miles · WI

The car will suddenly and without warning accelerate to 5000 RPM's. Had throttle body and mas replaced which seemed to help. However, it still happens once in a while (once every 3 weeks average). Usually happens after shifting from park to drive and driving forward at low speeds (around 5-10 MPH). Hasn't happened at higher speeds. Was told by one mechanic that the computer is defective???.

Filed Sep 27, 2013 · Acceleration, Brakes · 39,000 miles · AR

Car speeding up while braking.

Filed Aug 26, 2013 · Acceleration, Brakes · 87,500 miles · MA

When reversing out of driveway car accelerated on its own. Pressed brakes but car still moved backwards. Have skid marks in driveway to show for it. Threw car into neutral and turned off engine. Restarted and everything seemed normal. Drove car on trip and when reducing speed to slow down by pushing on brake car again accelerated and nearly hit another car. Again threw car into neutral and turned off engine. And again when restarting car everything seemed normal again. Wife is extremely afraid of driving car. Took car to dealer where it was purchased and was told that it may have been that I pushed the brake and gas pedal at the same time, this however, I believe is not the case. Dealership however kept the car for further investigation as to what the problem may be. Will hear in a day or two.

Filed Aug 15, 2013 · Acceleration, Brakes · 56,150 miles · GA

Vehicle was purchased used in june, 2011. While braking for a stop light, vehicle suddenly accelerated. Had to forcefully pump brakes to stop vehicle from hitting vehicle in front. Car returned to normal operation as soon as I got it stopped. Have had similar incidents a couple of times before, although not as bad as this one, however, at that time I thought maybe I had accidentally pressed the accelerator while braking. I know that was not the case this time.

Filed Jun 25, 2013 · Acceleration · 17,869 miles · KY · crash

Tl* the contact owns a 2008 mercury grand marquis. The contact stated that while depressing the brake pedal and driving approximately 5 MPH, the RPM reading increased as the vehicle jerked forward. The contact stated all the warning lights on the instrument panel illuminated. The failure recurred various times causing a crash. The contact was driving approximately 60 MPH when the vehicle accelerated, causing the contact to crash into a guard rail and a concrete wall. The police reported to the scene and a report was filed. The vehicle was towed to the dealer for diagnosis where the technician was unable to diagnose the failure. The manufacturer was made aware of the failure. The vehicle was not repaired. The approximate failure mileage was 17,869.

Filed May 25, 2013 · Acceleration, Engine · 86,000 miles · IN

I was driving on the interstate going about 65 MPH. I accelerated rapidly to pass a semi when I was getting close to my exit. After passing the semi I let my foot off of the accelerator but the vehicle did not slow down. I applied the brake pedal but the vehicle kept accelerating for about 5 seconds. After that I heard an audible "clunk" come from the engine compartment and the vehicle returned to normal operation. This is the second time this has happened the first was a month ago accelerating rapidly from a stand still position. In neither case did I wreck or get a speeding ticket.

Filed Feb 10, 2011 · Acceleration · 4,500 miles · IL

Tl*the contact owns a 2008 mercury grand marquis. The contact stated that while using the cruise control, applying the brakes and resuming to normal the vehicle suddenly accelerated to higher speeds. The vehicle stopped after the brake pedal was applied. The vehicle was inspected by a dealer who was unable to diagnose the failure since they were unable to duplicate it. The vehicle was not repaired. The failure mileage was approximately 4,500.

Filed Jul 27, 2010 · Acceleration · 500 miles · MO · crash · 2 injuries

Tl* the contact owns a 2008 mercury grand marquis. The contact stated he started the vehicle and when depressing the brakes, the vehicle abnormally accelerated. The contact was unable to stop the unintended acceleration and the vehicle drove over a curb and crashed into a sign. The contact and passenger both sustained minor injuries to their necks from the seat belt. The vehicle sustained substantial front end damages. The vehicle was towed to the dealer and inspected but the cause of the unintended acceleration failure was not disclosed to the contact. The body damage was repaired and the contact traded the vehicle fro another. The failure and current mileages were 500. Updated 10/01/2010. *lj updated 10/04/10

Filed Jul 7, 2010 · Acceleration · 42,000 miles · VA · crash · fire · 1 injury

Tl*the contact owns a 2008 mercury grand marquis. After driving in reverse and shifting into drive from a stop light the vehicle surged forward and crashed into another vehicle. A police report was not filed. One person was reported injured. Smoke was seen coming from under the hood of the vehicle. The vehicle was towed to the contacts residence. The failure had not been diagnosed by the dealer. The failure and current mileages were 42,000.