Huge win for car owners! All TSBs to be made public. The Center for Auto Safety just made the NHTSA (US Government) make public the full text of all TSBs from now on. They are the same organization that has petitioned the NHTSA & filed lawsuits to protect car owners over exploding gas tanks & other major safety issues. Whenever you drive in your car, you are safer thanks in part to a lot of work over the years by this small but very effective consumer advocacy group.

Please take a moment & say thank you by donating $5 or whatever you can to the Center for Auto Safety.


really awful
Crashes / Fires:
2 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
4,041 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.

2005 Mercury Grand Marquis engine problems

engine problem

Find something helpful? Spread the word.
Get notified about new defects, investigations, recalls & lawsuits for the 2005 Mercury Grand Marquis:

Unsubscribe any time. We don't sell/share your email.

2005 Mercury Grand Marquis Owner Comments

problem #5

May 212007

Grand Marquis 8-cyl

  • Automatic transmission
  • 20,194 miles


The contact owns a 2005 Mercury Grand Marquis. While driving 15 mph and making a right turn, the engine failed and the vehicle lost power. The vehicle was struck on the rear bumper by another vehicle. A few minutes later, the contact was able to restart her vehicle and drove to a mechanic. Due to a computer issue, the mechanic was unable to diagnose the cause of failure. The next day, the dealer diagnosed the cause of failure as problem with the throttle body, but did not repair the vehicle. The failure has caused the contact to have panic attacks and to seek a physician for medication. She has not driven the vehicle since. The current and failure mileages were 20,194.

- Leoma, TN, USA

problem #4

Jun 282006

Grand Marquis 8-cyl

  • Automatic transmission
  • 10 miles
Knocking noise from engine/transmission area when car is stopped at idle, transmission in gear, windows closed and heater fan off. Problem: Intermittent, erratic, muffled knocking noise. Heard from inside the car.

- Rockford, IL, USA

problem #3

Jan 152006

Grand Marquis 8-cyl

  • Automatic transmission
  • miles
This car has a dangerous defect. Randomly when in a stationary position, by holding the brakes, the engine and transmission sometimes suddenly accelerates powerfully, making it difficult to hold the car. I notified the dealer about this defect, several times in writing and by phone. Dec, 29, 2005 they took it on a drive, and claimed to have found no defect. Subsequently, Jan, 15, 2006 at approximately 1:00 pm, I was stopped at a red light on grand St. Nyc behind an SUV, by holding the brakes, all of a sudden it accelerated, and it was impossible to hold the car. It slammed into the SUV in front of me, smashing my front. Luckily, the SUV was not damaged. But even more luckily, we did not get hurt, (I had in the car my wife, an adult daughter, and 2 grand children). In addition, I guess we were extra lucky that we had the SUV in front of me, which averted a catastrophic mowing down of pedestrians crossing. The dealers took in the car, and notified me yesterday, Jan, 19, 2006, that they ran tests and find nothing wrong with the car.

- Brooklyn, NY, USA

problem #2

Jul 262005

Grand Marquis 8-cyl

  • Automatic transmission
  • 0 miles
Rough engine idle, dealer reps say "all the new ones do it", "it's normal". I have asked them about it on several occasions since purchasing the car. My 2005 marquis does not get nearly the good gas mileage the 2001 marquis did with the same engine. The dealer told me "you can't compare cars".

- Beggs, OK, USA

problem #1

Jul 262005

Grand Marquis 8-cyl Diesel

  • Automatic transmission
  • 0 miles
Rough engine idle, dealer reps say 'all the new ones do it', 'it's normal'. I've asked them about it on several occasions since purchasing the car. Not nearly as good gas mileage as our 2001 Grand Marquis got, was told by the dealer, "you can't compare cars'.

- Beggs, OK, USA

Not what you are looking for?