Check Engine Light due to worn spark plugs on Ford Expedition

Problem Description and Possible Solution

An illuminated Check Engine Light may indicate that the spark plugs are worn; this will cause intermittent misfire and damage to the coil packs.

Problem Data
RepairPal Verified
Average mileage: 172,742 (117,000–240,000)
Engines affected: 4.6L V8, 5.4L V8
9 model years affected: 1997, 1998, 1999, 2000, more2001, 2002, 2003, 2004, 2005
22 people reported this problem
Viewing 1 - 5 of 5 comments
Changed spark plug
Rough idle and hesitation. Cleaned PCV and found a crack in the elbow that attaches to the trottle body. New hose and problem gone.
Check engine light is blinking. On and off. No passing speed. Vehicle is heavy
changing spark plugs - the old ones have over 100K on them
Code cylinder 8 & 4 misfire. Changed coil & spark plug on 8 & 4. Then code cylinder 7 * 3...changed...then code cylander changed all. Then code for crank shaft sensor...changed it. Now code for MAF Sensor.