NHTSA — Engine Problems

10.0

really awful
Crashes / Fires:
0 / 1
Injuries / Deaths:
0 / 0
Average Mileage:
90,525 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.

2004 Mercury Grand Marquis engine problems

engine problem

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2004 Mercury Grand Marquis Owner Comments

problem #4

Sep 082021

Grand Marquis

  • miles

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

While driving, I came to a stop light and suddenly, the car idled high and lurched forward while my foot was on the brake, luckily, I was stopped well away from the vehicle in front of me. The car idled high and seemed to have a mind of it's own. I took the back roads home and backed into our garage. The car smelled hot, and I though I had smoked my brakes, trying to keep control of it. Later that night, I told my husband about the car's actions and he did not believe me, though my daughter who was with me at the time confirmed that the car had indeed accelerated on it's own. My husband started the car and it did idle high and get hot once again, although only parked with no one in it. He thought he knew what the problem was and we turned off the car and closed the hood and went inside to order the part. A few minutes later, we heard a couple popping noises and I opened the door that led into the garage from the basement. Smoke was coming into the house and my husband said that a flame shot over my head. The car had caught on fire under the closed hood. We called the fire department, but by the time they arrived, a good portion of the basement was on fire. The house was a total loss. My husband though that the pvc elbow under the hood was sticking closed, so that is the part we were going to order. Unsure, if that was the real cause or not. The car did not have any warning lights or any other indications of a problem before this incident.

- Brooklyn, MI, USA

problem #3

Jan 032018

Grand Marquis

  • 101,100 miles
I was driving at a speed of 45mph on a county road in rush hour traffic when my car's engine light came on simultaneously as power of vehicle slowed while making a rattle type noise and cab smelled strongly of gas. I rolled windows down pulled over within a block to a Napa store. The employee told me they do not run diagnostics and I would have to take it somewhere. I drove slowly to a 2nd auto parts store 1 mile away to run diagnostics. Once done, diagnostics identified a miss-fire on spark plug #2. had vehicle towed to home and took 'heli-coil' off and spark plug came out with it damaged. The heli coil was also damaged. The threads of spark plug was flattened three threads from bottom. Contacted auto parts store again where the technician told me that Ford has been having problems with there Triton spark plugs blowing out on the 5.4L engines that they only screw in 3 threads into the head of the engine and there were pending lawsuits. The next day I called Ford dealership and spoke with the acting service manager. "he told me there was nothing he could do about it and I should call customer care of Ford: 800-392-3673. I did and rep. Told me there was no recall and my vehicle and it was out of warranty at 101,100.mi. There was nothing they could do. In the event there were to be a re-call to save my receipts and Ford would reimburse me. I read about the problems that multiple customers were or had had regarding the same problem with a few vehicles leaking gas with the problem. This is all happening when the cars, trucks and SUVS exceeds 100,000miles. I feel this is not only poor manufacturing of an inferior aluminum casing and spark plug and also not enough threads to hold the spark plug in safely. To have it jump out allows gas to also be expelled onto the cars remaining parts and vapors could ignite causing the car to potentially catch fire.

- Lutz, FL, USA

problem #2

Sep 152014

Grand Marquis 8-cyl

  • 176,000 miles
The left hand (driver side) heat shield that covers the exhaust manifold has completely rusted at the bolting points causing the cover to dislodge and drag against the steering shaft. Several times while turning at intersections, especially when making left turns, the steering would temporarily lock up for a few seconds making turning extremely hazardous. Once I almost struck another vehicle due to the steering being locked while turning. I initially suspected low power steering fluid but fluid checked correct and pump seems to be working fine. I did not notice the rusted cover pinned between the steering shaft and manifold until I removed the engine cover and air intake tubing to access the spark plugs. I removed the rusted shield and the car turns just fine now. I have the rusted shield available for inspection if needed. Thanks

- Brunswick, OH, USA

problem #1

Oct 052013

Grand Marquis 8-cyl

  • Automatic transmission
  • 85,000 miles
The contact owns a 2004 Mercury Grand Marquis. The contact noticed that the vehicle continuously leaked coolant. The vehicle was towed to the dealer where they stated that the intake manifold needed to be replaced. The vehicle was repaired. The manufacturer was notified, but did not disclose that the part was modified from plastic to metal. The contact experienced multiple leaks before the part was modified to metal. The approximate failure mileage was 85,000. Remailed 08/18/14 updated 9/18/14 updated 02/11/2015

- Melbourne, FL, USA

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