10.0

really awful
Crashes / Fires:
12 / 1
Injuries / Deaths:
8 / 0
Average Mileage:
25,944 miles

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problem #32

Nov 022023

Grand Marquis

  • miles
I was driving I pressed the cruise control to set it but the vehicle kept accelerating and as I was pressing on the brake it wouldn-??t disengage it kept accelerating I kept pressing the brake frantically and THANK GOD it disengaged.. I never touched the cruise control again

- Staten Island , NY, USA

problem #31

May 092019

Grand Marquis 8-cyl

  • Automatic transmission
  • 79,000 miles
The contact owns a 2005 Mercury Grand Marquis. While driving 45 mph, the contact attempted to brake, but the vehicle accelerated. The contact shifted the transmission into neutral and the vehicle stopped. The engine continued to rev for awhile and then the rpms slowed down to a normal level. The contact stated that the symptoms disappeared on their own and the vehicle operated without any failures since. The manufacturer stated that there was no recall for the failure. The failure mileage was 79,000.

- Greenville, NC, USA

problem #30

Jan 082018

Grand Marquis

  • 24,500 miles
The vehicle will not disengage cruise when applying the brakes at 50 mph on the highway. In fact it will continue to accelerate until I hit the brakes hard. I have recently disconnected the system, what a shame. I am the 2nd owner. I purchased this vehicle in Sept 2017 with only 20,109 miles.

- West Covina, CA, USA

problem #29

Feb 022018

Grand Marquis

  • 35,000 miles
This has been a dangerously recurring engine accelerating problem while at rest or moving/coming to a stop on streets or highways but always while attempting to brake or hold in place. The brakes won't stop it, only turning off the ignition and restarting works. Barely avoided several accidents, so far. My Ford dealer has inspected the systems and my foot placements with out finding a problem or a solution. There are over 30 complaints regarding this problem in your database, some with serious injuries. After all these years, how can this issue be escalated before there is a fatality? please respond asap.

- Elgin, IL, USA

problem #28

Jan 192018

Grand Marquis

  • 39,000 miles
The contact owns a 2005 Mercury Grand Marquis. While driving approximately 5 mph and then depressing the brake pedal to slow the vehicle down, the vehicle accelerated without warning. To avoid crashing into the preceding vehicle, the contact was able to veer to the right and continue driving. There was no warning indicator illuminated. The failure recurred three times. The vehicle was taken to porter Ford (600 ogletown rd, newark, de 19711) where it was diagnosed that the throttle body motor assembly was sticking and needed to be replaced. The vehicle was repaired. The manufacturer was not contacted. The approximate failure mileage was 39,000.

- New Ark, NJ, USA

problem #27

Jun 212017

Grand Marquis

  • miles
Vehicle at times with my foot on the brake pedal, just starts to accelerate for no reason when I stop a light or in traffic.

- Brooklyn, NY, USA

problem #26

Sep 202016

Grand Marquis 8-cyl

  • 146,784 miles
The contact owns a 2005 Mercury Grand Marquis. The contact stated that while stopped at a traffic light, the vehicle accelerated independently. The contact stated that it became difficult to keep the vehicle from moving forward. The contact stated that the brake pedal was depressed but failed to stop the vehicle. The contact was able to slow the vehicle by placing the shift lever to the neutral position. The vehicle was not taken to be diagnosed or repaired. The contact stated that the failure was intermittent. The manufacturer was notified of the failure. The approximate failure mileage was 146,784. Updated 01/05/17

- Kearney, NE, USA

problem #25

May 132015

Grand Marquis

  • 87,000 miles
Unintended accel. Sometimes when I step on the brake the car accelerates instead. At first I thought it was me and my big feet. After some internet research I find it may be common as the 2005 gets older. I asked if brke pedal could be adjusted so that there was no interference with the gas pedal, I was told no. I had the master cylinder replaced, minimum improvement. One day I "shot" across US19 in ross township when I braked. Instead of stopping at a red light, I kept going until I cleared traffic in both directions ruining 2 wheels & tires - subsequently repaired. The car now sits in our driveway, after some other occurrences without incident. I'm leary of driving it & don't want to sell it & get someone injured or killed. Fortunately I have a 2004 Sable which I drive daily with no such problems! ideas?

- Pittsburgh, PA, USA

problem #24

Nov 092015

Grand Marquis

  • 144,000 miles
The contact owns a 2005 Mercury Grand Marquis. The contact stated that the vehicle failed to accelerate over 60 mph. When the vehicle was able to reach speeds more than 60 mph, the traction control warning light illuminated intermittently. The vehicle was taken to an independent mechanic where the failure was undetermined. The vehicle was not repaired. The VIN was not provided. The manufacturer was not notified of the failure. The approximate failure mileage was 144,000.

- Philadelphia, PA, USA

problem #23

Dec 292014

Grand Marquis

  • 40,000 miles
Started vehicle to move it in my driveway. Put it in drive and throttle stuck open and vehicle slammed my garage corner. Tried putting it in park and it went into reverse (brake override did not work) instead and crossed street, went across neighbors landscaping stones and slammed into the house next door's front porch at which time the ignition shut down and the car came to a stop. Many thousands of dollars in damages to all three homes.

- Mckinney, TX, USA

problem #22

May 072007

Grand Marquis 8-cyl

  • 12,000 miles
Sudden acceleration. The car did this after starting it in the driveway. Upon placing the car in drive the car accelerated burning rubber in the driveway. Had to stand on brakes and turn ignition off to stop car. The second incidence happened while braking for a red light, I had to shift car into neutral to stop car. Unsure of mileage in this instance. Most recently while in South Carolina I was sitting at a red light with my foot on the brake the car suddenly accelerated and I had to shift to neutral to avoid rear ending car in front of me. (mileage 60,000).

- Essex, MD, USA

problem #21

Apr 152013

Grand Marquis

  • 15,000 miles
The contact owns a 2005 Mercury Grand Marquis. The contact stated that the lights intermittently turned on and off. The contact took his vehicle to an independent mechanic where they replaced the lcm light control module. The manufacture was notified and stated that there was no recall for the make and model. The contact also stated while driving the cruise control suddenly malfunctioned spontaneously. The contact again took to vehicle to a Ford dealer were they stated there was nothing wrong with the vehicle. The vehicle was not repaired. The manufacture again stated no there were no related recalls for his year, make and model vehicle. The approximate failure mileage was 15,000 miles.

- Elgin, IL, USA

problem #20

Feb 102013

Grand Marquis

  • 25,000 miles
The contact owns a 2005 Mercury Grand Marquis. The contact stated that the vehicle exhibited sudden acceleration and the engine rpms would idle abnormally very high seconds prior to the failure occurring. The contact was able to stop the vehicle by shifting into neutral. The contact took the vehicle to the dealer however, the dealer was unable to diagnose the failure. The dealer then recommended having the throttle body replaced but could not guarantee that the repair would remedy the failure. The failure mileage was 25,000.

- Pompano Beach, FL, USA

problem #19

Oct 072010

Grand Marquis

  • miles
The contact owns a 2005 Mercury Grand Marquis. The contact stated that the vehicle suddenly accelerated whenever the contact was braking to a stop. The failure recurred several times. The vehicle was not taken to the dealer. The failure mileage was unknown and the current mileage was 46,000.

- Leesburg, FL, USA

problem #18

Jul 052012

Grand Marquis

  • miles
The contact owns a 2005 Mercury Grand Marquis. The contact stated that the driver of the vehicle was traveling 10 mph when the vehicle accelerated up to 50 mph and the driver crashed into several trees. The vehicle was not destroyed and there were no injuries. The vehicle was towed to a repair shop but the cause of the failure was unknown. The manufacturer was not notified of the incident. The failure mileage was unknown. The VIN was unavailable.

- Hot Springs, AR, USA

problem #17

Jun 162012

Grand Marquis

  • 18,000 miles
The contact owns a 2005 Mercury Grand Marquis. The contact stated that while parking, he attempted to apply the brakes but depressed the accelerator pedal instead. The contact crashed against another vehicle as a result. There was no damage. The contact stated that the failure was due to how close the pedals were positioned to one another. The vehicle was taken to dealer, who offered no assistance. The manufacturer was not notified. The VIN was not available. The failure and current mileages were 18,000.

- Vermilion , OH, USA

problem #16

Jan 092012

Grand Marquis 8-cyl

  • miles
Upon starting up 2005 Mercury marquis (~24000 miles) and placing car into drive, car accelerated at a high rate of speed and crashed into a gas station pump. The car accelerator malfunctioned and was in a "jammed state". the driver immediately put right foot then both feet on brake trying to get the vehicle to stop. The car would not slow much less stop. Driver suffered very serious eye injury and currently has no sight in injured left eye. There is the risk of losing left eye. Passenger suffered fractured sternum and other bruising. Both driver and passenger are traumatized from this car accelerator malfunction.

- Spring Lake, NJ, USA

problem #15

Oct 012005

Grand Marquis

  • 150 miles
The contact owns a 2005 Mercury Grand Marquis. The contact stated that while driving at any speed and attempting to brake, the vehicle suddenly accelerated. The failure was experienced numerous times. The vehicle was taken to the dealer several times for the failure where the dealer test drove the vehicle, but was unable to duplicate the failure. The vehicle was then taken to a local mechanic for further inspection. The contact also experienced failures with the headlights. The headlights were replaced but the abnormal acceleration failure was not repaired. The VIN was not available. The failure mileage was 150 and the current mileage was 15,600.

- Longwood, FL, USA

problem #14

Sep 152005

Grand Marquis

  • 5,000 miles
The contact owns a 2005 Mercury Grand Marquis. While driving at approximately 10 mph and depressing the brakes, the vehicle suddenly accelerated until the brake pedal was released. Also, while parked, the contact depressed the brakes and the vehicle lunged forward. The failure recurred intermittently. The vehicle was not taken to the dealer for diagnostics or repairs. The VIN was not available. The approximate failure mileage was 5,000.

- Bel Air, MD, USA

problem #13

Feb 242011

Grand Marquis

  • 8,770 miles
The contact owns a 2005 Mercury Grand Marquis. While driving approximately 44 mph, the contact applied the brakes and there was an abnormal increase in engine rpms and the engine roared loudly. The vehicle attempted to accelerate but the contact applied the brakes abruptly. The vehicle then gradually began to decelerate to approximately 30 mph. He then disengaged the overdrive feature and once the vehicle reached a speed of 30 mph, the vehicle operated as normal. The vehicle was not taken to have the failure diagnosed or repaired. The failure and current mileage was 8,770.

- Elgin, IL, USA

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