There are 2 owner-reported powertrain & transmission complaints for the 2007 Mercury Grand Marquisin NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
I WAS DRIVING THE VEHICLE. AS I STARTED UP A HILL THE SPEED LIMIT CHANGED. I GAVE THE GAS PEDAL A LITTLE PUSH. IT WENT TO THE FLOOR WHERE IT STUCK WIDE OPEN. THE CAR LEAPED FORWARD AND I IMMEDIATELY APPLIED THE BRAKE. I REALLY HAD TO PUSH THE BRAKE AS HARD AS I COULD TO GET THE VEHICLE TO STOP. WHEN I GOT THE VEHICLE TO STOP I KNOCKED THE GEAR SHIFT OUT OF DRIVE INTO NEUTRAL. THE ENGINE WAS IDLING REALLY ROUGH BUT THEN IT SMOOTHED OUT. I DID NOT CRASH THE CAR AND CONTINUED DRIVING WITH NO FURTHER PROBLEMS. THE VEHICLE HAS 64,875 MILES ON IT AND THIS IS THE FIRST THIS HAS HAPPENED.
TL*THE CONTACT OWNS A 2007 MERCURY GRAND MARQUIS. WHILE DRIVING APPROXIMATELY 35 MPH AND PROCEEDING TO A COMPLETE STOP, THE VEHICLE SURGED FORWARD WHEN THE BRAKE PEDAL WAS DEPRESSED. THE CONTACT DISENGAGED THE CLUTCH AND MOVED THE GEAR SHIFTER TO THE "PARK" POSITION. THE VEHICLE WAS ABLE TO BE DRIVEN TO THE CONTACT'S RESIDENCE. THERE WERE NO WARNING INDICATORS ILLUMINATED ON THE INSTRUMENT PANEL. THE AUTHORIZED DEALER WAS NOTIFIED AND SCHEDULED AN APPOINTMENT FOR A DIAGNOSTIC TESTING. THE CONTACT WAS CONCERNED OF THE SAFETY RISK INVOLVED. THE CURRENT AND FAILURE MILEAGES WERE 29,430.
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 25, 2026