Which parts fail
Components named in complaints (engine, cooling system, oil leaks, timing chain, exhaust).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 1997 Mercury Grand Marquis owners, lightly cleaned up (personal details are redacted by NHTSA).
Tl* the contact owns a 1997 Mercury Grand Marquis. While driving at speeds of 10 MPH, the contact observed smoke coming from under the hood and within seconds, the interior cabin was filled with smoke and flames. The vehicle occupants were able to safely exit the vehicle. And the fire and police department were contacted. There were reports filed by both entities. The vehicle was destroyed. The dealer advised there were no recalls for the vehicle and the manufacturer would not provide any assistance. The failure and current mileages were 37,000.
Coolant leak from crack in plastic intake manifold. This car only has 97,130 miles on it and well cared for. They should not be using plastic in this application - it should be iron or aluminum. This is a common problem I was told with the 4.6 v8 engine. Ford needs to recall these and replace at no cost to customer. I will be writing a letter to Ford if the dealer doesn't cover this as a recall. Ridiculous to use plastic in this application.
Driving with my family, on an interstate at 65 MPH, we suffered a catastrophic loss of engine coolant. Thank god, I managed to safely pull over to the shoulder of the road. The vehicle was towed 25 miles to the nearest Ford dealer to natural bridge, virginia. I was dumbfounded when I learned that the manifold was made of plastic; it actually blew apart, releasing all the engine coolant at once. Additionally, I learned that not only did Ford engineer an inferior major engine component, but they made my family the guinea pig to field test this junk! To add insult to injury, they made me pay for it. My cost included: towing $125, manifold replacement for $800, and an unplanned hotel stay including meals for approximately $225 with a total cost of $1150 which does not include the loss of a days pay. …
Driving down highway at 60 MPH., when the plastic intake manifold suddenly ruptured dumping out all the antifreeze. High volume of traffic, we could barely get off highway, steam coming from my car blocking vision. Could have caused a major accident. Car had to be towed to local garage, then towed to my home and local garage for repairs. We had to rent car to get home. Mechanic said our intake manifold ruptured causing head gasket failure and possible engine failure. On 8-23-05, got class action suit papers in mail stating plastic intake manifolds could rupture causing coolant to leak and Ford would reimburse people who had the problem and paid for repairs. When I got the paper I went to mechanic and told him to stop repairs to see where I stood in suit. Suit did not mention gasket repair reimbursement and engine failure reimbursement. …
I was driving my father's 1997 Mercury Grand Marquis ls at 35 MPH. I noticed a car pull up beside me with the driver waiving frantically. I rolled down my window and he told me my car was "pouring water". I looked at the temperature gauge and it had risen. Managed to make it the five or so blocks to the house and raised the hood. Steam came out. Filled with water and took to a local shop on Monday morning to find out the car had a cracked intake manifold. Repair bill for intake was $800 with more to come as now it has noisy lifters. There was a recall and class action suit as my 1997 cougar had 3 intakes replaced, one the manufacturer reimbursed under recall. They would not pay for the other two but they sent me the same faulty part on the second go round. On my car and this Grand Marquis, mileage was right at 80,000 on first occurrence. …
My wife, and I were comeing home, after eating lunch, going about 50 MPH, when a big cloud of smoke,steam come from the motor compartment," I almost hit a on comeing car, because the smoke, and steam was so "sudden, and thick". I pulled over as soon as possible, to find anti-freeze all over the motor compartment, and all under neith the car, even on all (4) tires. If we had been on a much busyer hwy, some one could have easily gotten hurt, are killed ! After getting a car hauler to take the car to my home, we found out the manifold was a defected part on the fault of the manufacturer of the manifold ! This is a part that is defected, not warn-out. My car does`nt have but 77,000 miles," I know the problem has been corrected," but "who" is going to fix my car? The lowest estimate was $624.00 ! …
A few months ago we found that our was over heating and found that we are leaking water somewhere in the system. We could not find a leak but had to put water into the radiator ever two days. We took the car to the shop to have the pros find the leak. We were told that their was w crack in the intake manifold and that it was a very common defect in Ford & Mercury Grand Marquis. They said that the manifold was made of plastic and they would all crack and brake. Every shop that I went to said the same thing and that they a lot of Grand Marquis waiting to be repaired. A replacement manifold cost $400.00 plus $250 in labor. We were told that if we continued to drive it, it would blow-up. We are afraid to drive the car and the parts are not available. I saw at least 20 Grand Marquis waiting for manifolds. I was told that Ford design them to brake. That's why their made of plastic. …
Just left highway rest stop in kentucky, no signs of coolant leakage or any problems. Within 5-7 miles at 65mph, a beep, beep sound, then temperature gauge rose immediately to high , began to slow vehicle & turned heater on. Steam was scene from under the hood as we approached a construction area. We barely made it to a closed weigh station. Failure was sudden & catastrophic. Had we remained on the highway, an accident would have surely occurred, no shoulder was available. Two hours waiting for a tow truck, which finally took the vehicle to the nearest Ford dealer. Being a Sunday, we had to obtain overnight stay in a hotel. Monday the dealer diagnosed the problem as a cracked intake manifold. Dealer replaced the part, including thermostat & coolant. Dealer kept the old parts. Dealer said no recall was made for this part. …
97 Mercury Marquis gs, it has 91K mi on it. The intake manifold failed unexpectedly with a crack in the plastic coolant crossover. The coolant sprayed all over inside of engine compartment. It was the weekend I was on a rural highway in the sticks with my two kids ages 4 & 6 in the car somewhere between boston & the university of nh. Not wanting to become stranded in sub zero degree weather in the middle of no where, I managed to crawl it into the driveway of a local mechanic where it died & would not start, the motor was super hot! The mechanic added coolant managed to get the engine turn over after sitting for the weekend & called to tell me the plastic intake manifold was cracked & that is was not covered under recall by Ford. It cost me over $1200 for the expenses incurred as a result(parts & labor, hotel & rental car expenses). …
While driving MIL code p0420 set. Ford TSB 03-24-5 indicates PCM reprogramming rather than replacement of catalytic converters required. Despite being within emissions warranty coverage period dealer charged $119 for this work, claiming emissions warranty did not cover this work. Defective programming of PCM to cause the check engine light to come on, requiring a visit to dealer. Can't pass emissions test with light on, should be against the law. In any case the reprogramming of the PCM should have resulted in no charge. This failure resulted in a mandated, due to state emissions testing, visit to dealer and a charge for service to fix a manufacturing defect. The PCM was reprogrammed, according to dealer, and currently light is off. …
NHTSA investigations
Speed control deactivation switch fires
Based on the low rate of fire incidents (2.5 incidents per 100,000 vehicles sold) where failure of the scds is involved and the age of the vehicles ? 7 to 11 years ? A safety-related defect trend has not been identified and further use of agency resources does not appear to be warranted.the closing of this investigation does not constitute a finding by NHTSA that no safety-related defect exists.the agency reserves…
Spark plug ejection from cylinder head
On September 6, 2005, odi received a petition requesting that the agency investigate allegations of engine spark plug ejection in certain model year 1997 through 2004 Ford vehicles with triton v-8 and v-10 engines.odi received a total of 474 non-duplicative complaints on the subject vehicles where the complainant, or the dealer repairing the vehicle, reported that a spark plug detached from the cylinder and/or…
Engine complaints in other Grand Marquis years
Frequently asked questions
How common are engine problems on the 1997 Mercury Grand Marquis?
NHTSA has 126 complaints about the engine & cooling of the 1997 Mercury Grand Marquis, 40% of the model year's 316 complaints. The component named most often is exhaust system › manifold/header/muffler/tail pipe (55 mentions).
Is there a recall for 1997 Mercury Grand Marquis engine problems?
No. NHTSA lists no engine & cooling recall for the 1997 Mercury Grand Marquis, though it has 4 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 1997 Mercury Grand Marquis engine problems start?
Half of the complaints with a recorded mileage happened before about 81,000 miles, and 1% before 25,000 miles.
Is it dangerous?
Owners linked 1 crash, 3 fires and 2 injuries to engine & cooling problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.