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10.0

really awful
Crashes / Fires:
8 / 0
Injuries / Deaths:
6 / 0
Average Mileage:
51,284 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 #17

Jan 152016

Grand Marquis

  • miles

A D V E R T I S E M E N T S

Unexpected acceleration when car is stopped at a light, car lunges forward. On one occasion the car was burning rubber. Very dangerous and scary. Have to shut off ignition when this happens. Has occurred several times. My wife refuses to ride in the vehicle.

- Plainfield, IL, USA

problem #16

Oct 082014

Grand Marquis 8-cyl

  • Automatic transmission
  • 130,000 miles
The contact owns a 2003 Mercury Grand Marquis. The contact stated that while driving 20 mph, the brake pedal was depressed and the engine rpms increased approximately to 4000. The contact stated excessive force was applied to the brake pedal and the vehicle jerked. The brake pedal was aggressively depressed until the brakes responded and the vehicle was able to come to a stop. The vehicle was taken to the dealer where the failure was unable to be diagnosed. The vehicle was not repaired. The manufacturer was notified of the failure. The approximate failure mileage was 130,000. The consumer stated when he applied the brakes, the vehicle slowed down. However, the engine speed increased to 4,000 RPM's/ with the brake fully depressed, the vehicle continued with a series of lunges at a high speed. Only by releasing the brake pedal and slamming on the brake, did the vehicle stop about three quarters across the intersection with the engine at a normal idle speed. No warning lights displayed on the dashboard. The vehicle had a history of almost stalling while coming to a stop. The dealer did not find any codes. Updated 12/04/14

- Trinity , NC, USA

problem #15

Oct 142013

Grand Marquis

  • 147,696 miles
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.

- Washington , DC, USA

problem #14

Oct 122012

Grand Marquis

  • 100,000 miles

A D V E R T I S E M E N T S

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.

- Portageville, NY, USA

problem #13

Jul 122011

Grand Marquis

  • 50,400 miles
The contact owns a 2003 Mercury Grand Marquis. The contact stated was attempting to park the vehicle while driving 5 mph in a residential driveway when the vehicle abnormally accelerated. The contact crashed into the garage of his home. The brakes were applied during the failure but did not respond. The contact was uninjured yet there was extensive damage to the vehicle. The vehicle had not yet been inspected or repaired. The manufacturer was not notified of the failure. The failure mileage was 50,400.

- Johnsboro, TN, USA

problem #12

Jul 122011

Grand Marquis

  • 162,000 miles
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.

- San Juan, TX, USA

problem #11

Nov 172008

Grand Marquis

  • 50,000 miles

A D V E R T I S E M E N T S

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.

- Frankford, IL, USA

problem #10

Dec 012004

Grand Marquis

  • 20,000 miles
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 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.

- Moss Point, MS, USA

problem #9

Oct 162009

Grand Marquis

  • 25,000 miles
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.

- Roselle Park, NJ, USA

problem #8

Jun 092008

Grand Marquis

  • 44,500 miles
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.

- Cheula Vista, CA, USA

problem #7

Apr 122007

Grand Marquis 8-cyl

  • Automatic transmission
  • 58,000 miles

A D V E R T I S E M E N T S

The contact owns a 2003 Mercury Grand Marquis. While waiting to turn at a stop sign the engine increased in rpms and accelerated forward. The failure caused the contact's vehicle to crash into the vehicle in front of him. Both vehicles were damaged, and a police report was taken. The vehicle was at the dealer awaiting a diagnostic to determine the cause of failure. The contact was waiting for an insurance estimate and report. The current and failure mileages were 58,000.

- Bluffton, SC, USA

problem #6

Aug 012005

Grand Marquis

  • 1,000 miles
2003 Grand Marquis developed problems with the alternator, the throttle sticking open and alignment problems. There was also a rattle noise coming from the engine and the digital readout on the dash was not reading properly.

- Crestline, CA, USA

problem #5

Dec 012004

Grand Marquis 8-cyl

  • 20,397 miles
While stopped at a traffic light with foot on brake, the vehicle kicked into a fast idle.

- Hinckley, OH, USA

problem #4

Jan 182004

Grand Marquis

  • Automatic transmission
  • miles
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).

- Haworth, NJ, USA

problem #3

Oct 202003

Grand Marquis 8-cyl

  • 1,828 miles
Vehicle suddenly zoomed forward while leaving a parking lot. 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.

- Tamarac, FL, USA

problem #2

Sep 032003

(reported on)

Grand Marquis

  • 61,000 miles
When applying pressure to the brake, the accelerator surged.

- Gobles, MI, USA

problem #1

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

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