There are 8 stored owner reports matching the engine leading-label group for the 2005 Mercury Grand Marquis in our NHTSA-sourced dataset. These are unverified consumer reports and may not reflect confirmed defects.
This group counts stored reports whose component label starts with one of this site's matching prefixes, ignoring case. Each matching report counts once within the group. Components mentioned later in the label or only in the narrative are not searched. How component counts work
Loaded 8 of 8 matching reports.
Open the full vehicle complaint log (all categories)TL* THE CONTACT OWNS A 2005 MERCURY GRAND MARQUIS. WHILE DRIVING AT AN UNKNOWN SPEED, THE PLASTIC COVER OF THE INTAKE MANIFOLD FRACTURED AND LEAKED WATER ALL OVER THE YARD WITHOUT WARNING. THE DEALER WAS NOT CALLED. THE MANUFACTURER WAS MADE AWARE OF THE FAILURE AND INFORMED THE CONTACT TO CALL NHTSA. THE FAILURE WAS NOT REPAIRED. THE FAILURE MILEAGE WAS APPROXIMATELY 115,000.
2005 MERCURY GRAND MARQUIS. CONSUMER WRITES TO REQUEST REIMBURSEMENT *TGW THE CONSUMER'S CLAIM FOR REIMBURSEMENT WAS DENIED BECAUSE THE VEHICLE DID NOT HAVE ROADSIDE ASSISTANCE COVERAGE AND PARTS/LABOR WERE NOT COVERED BY ROADSIDE ASSISTANCE. THE SERPENTINE BELT AND LIGHTING CONTROL MODULE HAD TO BE REPLACED. *JB
TL*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.
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. *JB
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. *JB
ON THREE OCCASIONS WHEN SHIFTING FROM PARK TO REVERSE THE ENGINE SPED UP (ACCELERATED DRASTICALLY) CAUSING THE WHEELS TO SPIN AND ONLY BY QUICK APPLICATION OF THE BRAKE WAS AN INCIDENT AVOIDED. I DROVE INTO A PARKING SPACE, PUT THE CAR IN PARK, THEN NOT SATISFIED WITH THE POSITION I ATTEMPTED TO BACK UP, THAT'S WHEN THE CAR ACCELERATED. *JB
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". *NM
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'. *NM
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.
NHTSA source checks for this vehicle year
Checks are recorded separately for each dataset, not for the whole page. Dates use UTC. A missing check date does not mean no records exist.
Vehicle import recorded: Apr 28, 2026. This is the stored import date, not confirmation that every source was successfully refreshed.