2002 Mercury Grand Marquis Problems
RepairPal has identified the most common problems with the 2002 Mercury Grand Marquis based on complaints from actual vehicle owners. We'll tell you what the problem is and what it'll take to fix it.
The composite (plastic) intake manifold may crack near the thermostat housing and cause a coolant leak. Ford released an updated manifold that was reinforced to prevent a recurrence. No recall was issued for this problem but Ford did extend the warranty to seven years on some models from the date of purchase.
The throttle position sensor (TPS) may fail. Common symptoms of a defective TPS can be rough idle, hard starting, hesitation on acceleration, poor fuel economy, and stalling.
The alternator may get too hot, causing premature bearing failure.