There are 13 owner-reported engine complaints for the 2004 Mercury Mountaineerin NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
MY VEHICLE SHUTS OFF WHILE DRIVING. NO WARNING, LOSES POWER STEERING, LOSES POWER BRAKES. IT WILL START RIGH BACK UP ONCE I SHIFT INTO PARK. THIS HAPPENS AT ALL DIFFERENT SPEEDS AND TEMPERATURES. I COULD HAVE JUST GOT IN THE CAR OR BEEN DRIVING FOR HOURS. HAPPENS AT 15MPH AND 60MPH JUST THE SAME. HAVE ALMOST BEEN HIT FROM BEHIND OF SEVERAL OCCASIONS WHEN THIS HAS HAPPENED.
THIS VEHICLE IDLES VERY LOW AND STALLS AT VARIOUS SPEEDS. NO WARNING IS GIVEN ENGINE JUST SHUTS DOWN. SPARK PLUGS HAVE BLOWN TOTALLY OUT FROM THE ENGINE SEVERAL TIMES.
TL* THE CONTACT OWNS A 2004 MERCURY MOUNTAINEER. THE CONTACT STATED THAT THE VEHICLE SUDDENLY STALLED. THE VEHICLE WAS NOT DIAGNOSED OR REPAIRED. THE MANUFACTURER WAS CONTACTED ABOUT THE FAILURE. THE FAILURE MILEAGE AND VIN WAS NOT AVAILABLE.
04 MOUNTAINEER CLUSTER GAUGE BLACKS OUT THEN METER GAUGE FLICKERS. WAITED FOR 10 MIN I'M PARKING LOT THEN IT COMES ON. STARTED TO DRIVE THEN ABOUT A MILE INTO DRIVING IT SHUTS DOWN. MIND YOU MY SUV WAS STILL GOING BUT GAUGES SHUT DOWN THEN MY LIGHTS GO OFF, THEN MY WINDSHIELD WIPERS GO. BY THE GRACE OF GOT I GOT HOME. WHILE ON ROAD MY ENGINE WAS STRUGGLING. HELP BEFORE THAT INCIDENT I HAD JUST REPLACE THERMOSTAT HOUSING BECAUSE IT CRACKED AND I WAS LOOSING COOLANT. *TR
SHUT OFF WHILE DRIVING LOST POWER STEERING ETC. *TR
TL*THE CONTACT OWNS A 2004 MERCURY MOUNTAINEER. WHILE HAVING THE VEHICLE SERVICED FOR ROUTINE MAINTENANCE AT AN AUTHORIZED DEALER THE CONTACT COULD SMELL A BURNING ODOR. THE CONTACT WAS TOLD THE ENGINE MANIFOLD WAS CRACKED AND LEAKING. THE VEHICLE WAS REPAIRED. A FEW DAYS LATER THE VEHICLE BEGAN SHAKING WHILE STOPPED. THE VEHICLE WAS TAKEN BACK TO AN AUTHORIZE DEALER WHERE THE CONTACT WAS TOLD THE ENGINE COILS AND SPARK PLUGS NEEDED TO BE REPLACED. THE VEHICLE WAS REPAIRED. THE FAILURE AND CURRENT MILEAGES WERE 46,845. UPDATED 03/24/11*LJ UPDATED 1/4/11 *CN
2004 MERCURY MOUNTAINEER - HARMONIC BALANCER FAILED. IT WAS NOTICED WHEN A SQUEAKY NOISE WAS COMING FROM THE ENGINE. ALTHOUGH IS WAS CAUGHT BEFORE ANY SERIOUS INJURY OCCURRED, THIS FAILURE MAY HAVE LED TO ONE. IF THE BALANCER HAD COMPLETELY FAILED, IT COULD HAVE RESULTED IN LOSS OF STEERING AND AT HIGHWAY SPEEDS WOULD HAVE BEEN CATASTROPHIC. STEERING IS LOST BECAUSE DRIVE BELT WOULD HAVE COME LOSE. UNIT WAS REPLACED AT A COST OF $475. OLD PART WAS SAVED FOR INSPECTION. *TR
I STARTED MY 2004 MERCURY MOUNTAINEER THE OTHER DAY, AND THE ENGINE STARTED MAKING A HORRIBLE NOISE, LIKE A LAWN MOWER, RIGHT WHEN IT STARTED. I SHUT IT OFF IMMEDIATELY AND EVENTUALLY HAD TO GET A TOW TRUCK TO BRING ME TO THE FORD DEALER. LUCKILY I WASN'T DRIVING THIS TIME WHEN IT HAPPENED. IT TURNS OUT THAT THE ENGINE SPAT OUT A SPARK PLUG. THIS SEEMS TO BE A CHRONIC PROBLEM WITH FORD MOTOR COMPANY SUV'S AND PICK-UPS. THE TEMPORARY SOLUTION IS TO PLUG THE SOCKET BECAUSE THE THREADS WORE OUT. HOWEVER THE SPARK PLUG WAS FACTORY-INSTALLED AND THE ISSUE IS DEFINITELY A FORD PROBLEM. THE NEXT TIME, IT COULD BE EITHER LEAD TO A TERRIBLE ACCIDENT OR THOUSANDS OF DOLLARS TO REPAIR, OR BOTH. *TR
ON AUGUST 29, 2008, AT ABOUT 9:30 P.M., I WAS GOING HOME FROM A VACATION. I WAS GOING 55 MILES PER HOUR AND THE VEHICLE POWER COMPLETELY STOPPED. I WAS ABLE TO GET OFF THE FREEWAY SAFELY AND AFTER SEVERAL ATTEMPTS THE VEHICLE STARTED UP AGAIN. THIS WAS VERY FRIGHTENING BECAUSE WE TRY OUR BEST TO MAINTAIN THE VEHICLE TO ITS OPTIMAL I.E. OIL,TIRES. THIS NEEDS TO BE INVESTIGATED FURTHER BY THIS AGENCY AS SOON AS POSSIBLE. THANK YOU *TR
THE VEHICLE STALLS INTERMITTENTLY. THE CONSUMER HAS TAKEN THE VEHICLE TO THE DEALER AND WAS TOLD THAT THE PROBLEM DID NOT DUPLICATE ITSELF. *JB *SC
DT:THE CONSUMER STATED DURING BRAKING THE VEHICLE STALLS. WHEN THE CVONSUMER WENT TO RESTART AND PUT IT IN DRIVE IT STALLED AGAIN. TOOK VEHICLE TO THE SERVICE DEPARTMENT 3 TIMES. THE SECOND TIME THEY REPLACED THE FUEL PUMP, THE FIRST TIME THEY UPDATED THE ENGINE CONTROLLER SOFTWARE.*AK FOR THE 4TH TIME TOTAL LOSS OF VEHICLE POWER WHEN BRAKING FROM 55 MPH. DEALER REPLACED MAF SENSOR. DRIVER REAR DOOR MOLDING CATCHING FRONT DOOR MOLDING AT TIMES WHEN OPENING. *TT
WHILE DRIVING THERE WAS A VERY LOUD NOISE FROM THE FRONT OF THE VEHICLE. CONSUMER PULLED OFF THE ROAD, AND CALLED ROAD SIDE ASSISTANT. VEHICLE WAS TOWED TO THE DEALER, WHO PERFORMED AN OIL CHANGE BECAUSE OF MILEAGE AT THE TIME OF THE INCIDENT. NOISE RECURRED THE FOLLOWING DAY. VEHICLE WAS TAKEN BACK TO THE DEALERSHIP, WHO INDICATED THAT THE DRIVESHAFT WAS DEFECTIVE, AND NEEDED TO BE REPLACED. VEHICLE IS CURRENTLY AT THE DEALERSHIP BEING INSPECTED. *AK
WHILE DRIVING, THE ENGINE CHECK LIGHT ILLUMINATED ON THE DASHBOARD. CONSUMER TOOK THE VEHICLE TO THE DEALERSHIP (4) TIMES, BUT THE PROBLEM STILL EXISTED. *AK *JB
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 26, 2026