Engine complaints by model year
| Year | Complaints | Share of year's complaints | Typical mileage |
|---|---|---|---|
| 2010 | 3 | 23% | 55,000 miles |
| 2008 | 9 | 9% | 86,000 miles |
| 2007 | 9 | 11% | 67,000 miles |
| 2006 | 56 | 48% | 59,000 miles |
| 2005 | 12 | 15% | 73,000 miles |
| 2004 | 19 | 9% | 70,000 miles |
| 2003 | 11 | 7% | 85,000 miles |
| 2002 | 35 | 9% | 92,000 miles |
| 2001 | 2 | 9% | 130,000 miles |
| 2000 | 9 | 7% | 165,000 miles |
| 1999 | 12 | 8% | 53,000 miles |
| 1998 | 22 | 9% | 72,000 miles |
| 1997 | 14 | 4% | — |
Which parts fail
Components named in complaints (engine, cooling system, oil leaks, timing chain, exhaust).
Mileage when the problem started
What owners report
Pulled into parking space, placed shifter in park, turned off ignition, released brake and vehicle rolled backwards as if not in park. Attempted to restart vehicle and no response. Set parking brake. Could not get vehicle to lock into park, shifter moved regardless of brake on or not and would not start. Moved shifter through entire range of gears and returned to park, vehicle still would not start and park would not hold. Called dealer and was told to have it towed in. Returned to vehicle and tried once more and it started and proceeded to respond normally. Vehicle taken directly to dealer who could not find any problem or cause of preceding situation. On two subsequent dates (most recent 5/25/2012), vehicle was backed into a parking space, placed in park and ignition turned off. When an attempt to restart vehicle was made there was no response. …
While driving the Mountaineer I was slowing for a stoplight shortly after starting it up (had driven about 1/3 mile). The engine suddenly started to speed up and required significant extra braking force to come to a stop. I put the car in neutral and the engine ran at about 3,300 RPM for about 10 seconds. This is the third time this has happened. The first time the thermostat was replaced. The second time the throttle body was replaced. The third time the vehicle was checked but no defect could be found. The second time I also put it in neutral and it also ran at about 3,300 RPM for about 10 seconds.
The contact owns a 2008 Mercury Mountaineer. The contact stated that the check engine warning light was illuminated. The contact stated the vehicle stalled while driving at an undisclosed speed. The contact stated that several attempts were needed to restart the vehicle to continue driving. The contact stated that the gear shifter intermittently failed to move to the intended position. The contact stated that there was an abnormal fuel odor inside the cabin of the vehicle, and the fuel level was lowered sooner than normal. The vehicle was taken to the dealer to be diagnosed; however, the result was not provided. The contact stated that there was a code for an EVAP failure. The vehicle was not repaired. The vehicle was taken to another dealer, Peoria Ford (9130 W Bell Rd, Peoria, AZ 85382) however, the contact was not provided the cause for the failure. …
Since I purchased in 2009, engine kills anytime, mostly when gas pedal not pressed. Pulling out of parking lots, sitting at red lights, or letting off gas on interstate, engine just kills. Sometimes feels like a jolt. I have to put the shift in neutral and restart the engine. Records of all visits for the problem at dealership. Never could solve problem, but too unsafe to donate to my grandson. If something were to happen to him because of a defect that was never found, I don't know what I'd do. Cannot check transmission fluid level. Sealed. I do have some fluid stains on my driveway. For years I've reported to the dealership and specified the concern for safety but to no avail. It kills anytime. May not die for a week, or tomorrow, or even a month. No particular pattern. Feels like a transmission problem. If I'm sitting in a parking lot with motor running, sometimes it just kills. …
Car ran rough & hesitated/surged upon acceleration. Apparently this is a common Ford problem involving premature spark plug break down in the Ford triton engine see Ford spark plug class action settlement. Shultz Ford in nanuet ny diagnosed the problem as faulty plugs, there was also a risk of breaking plugs upon removal. I had them do the repairs at a cost of $788. Later I found that there was a settlement, however my car was not included even though it had the same engine as the cars/trucks/ SUV's that were included in the settlement. Ford customer service said there was nothing they could do re: reimbursing me for the repair expense as my SUV was not included in the settlement. They suggested I file this complaint. Can I get some satisfaction?
A repair shop told me that my engine was leaking coolant that could make the engine run hot and fail. After doing some online research, I found that this is a common problem with these vehicles as Ford used a cheap plastic part which easily cracks and allows coolant to leak. The leak also affects other parts of the engine cause them to perform improperly. Ford is aware of this problem but has failed to issue a recall despite their knowledge and the risks to the consumer.
The contact owns a 2006 Mercury Mountaineer. The contact stated that her husband informed her that the vehicle had experienced an unknown radiator failure. The vehicle was taken to an independent mechanic, where the radiator was replaced; however, the failure reoccurred. The vehicle was repaired for a second time by an independent mechanic; however, the failure persisted. The local dealer was made aware of the failure. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 143,869.
My 2006 Mercury Mountaineer was leaking coolant due to a crack in the radiator. After searching online forums, I have learned that has been a long standing issue with many of this vehicles owners. Unfortunately for owners, Ford issued a tbs in 2009 just in time for most of the affected vehicles' warranties to expire. Some owners are on their 3rd or more radiator replacement, I am only on my first. I petition that Ford recalls this issue before myself and others have to repeatedly pay for this clear design problem with their hard owned money. This problem also poses safety risk to the passengers operating these vehicles and to any animals attracted to the sweet smell of the coolant from affected vehicles whose owners who May not yet know this issue or cannot afford to fix it.
NHTSA investigations
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…
Frequently asked questions
Which Mercury Mountaineer years have engine problems?
By NHTSA complaints, the 2006 (56), 2002 (35), 1998 (22), 2004 (19) and 1997 (14) model years. Engine complaints make up 48% of all complaints for the 2006.
Is there a recall for Mercury Mountaineer engine problems?
No. NHTSA lists no engine & cooling recall for any Mercury Mountaineer model year. A widespread problem may still be covered by an extended warranty or a manufacturer service bulletin, so ask a dealer.
At what mileage do Mercury Mountaineer engine problems start?
Across all years, half of the complaints with a recorded mileage happened before about 77,000 miles; 28% happened before 50,000 miles.
What part fails most often?
Owners most often name the engine (30 mentions), followed by the cooling system (26).
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.