One problem related to speed control linkage has been reported for the 2003 Mercury Grand Marquis. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2003 Mercury Grand Marquis based on all problems reported for the 2003 Grand Marquis.
Vehicle suddenly zoomed forward while leaving a parking lot. On several occasions, the consumer experienced sudden acceleration with the vehicle. The dealership checked all the linkages and pedal assembly but was unable to diagnose the defect which caused this dangerous condition.