Vince, Dave, 911

[Blue Goose]

We have a '97 Expedition with a 5.4. Tonight on the way home it started to miss and the CEL light came on. It has 90,000 miles on it with less than 20,000 on a major tune up. Is there an at home way to check the coils?

 

[blacksnapon]

Not that I'm aware of. Its a little rough, but if you can pull the coils out and check for water intrusion in the plug holes. Thats where silicone dielectric compound comes in. A little smeared inside the "plug boot" might improve the situation.

 

[Blue Goose]

OK, thanks for the tip. We had a storm today so water intrusion may very well be the deal... I'll check it out.