spark plugs are fauling

[AC94EXPLORER]

i have a 94 ford explorer i ran autolites in them the first time i did a tune up and the plugs were fauled out 2500 miles. so i ran the bosch ones and now they are fauling out again i dont know whats the spark plug one the back passenger side had hard bubbles on it and it was black. drivers side back i was black. the drivers side plugs as you face them the first (left side) and second had gas on them. i was told by my mechanic that these 4.0's are picky on spaerk plugs and told me to run the motorcrafts. anyone have any sudjestions? i dont wanna keep changing out these plugs. tomorrow im buying the motorcrafts and we will see how long they last. could it be my coil pack?

[CMOS]

While most Fords like MC plugs, the Autolites should have been fine. It sounds like you have other issues.

When was the last time the plug wires were changed?
How many miles on the truck?
Have you done a compression test on each cylinder?

Yes, it could be the coil pack, or a combination of things. Start investigating them one at a time.

CMOS

[Bear River]

The spark plug wires are only good for 60,000- 100,000 miles, about the life of the plugs. The wires should be replaced. You can test the coil packs to see if the primary and secondary resistance is to spec.

Autolite makes the motorcraft plugs, so the Autolites should have been fine, assuming they were the correct double platinum plug. I have tried Bosch before, and never got more than a couple thousand miles out of them.

[AC94EXPLORER]

the wires has 3k on them. it's goin to the shop on monday. im gonna see if i can take my coil ouit and have it tested at autozone.

[CMOS]

YOU can take the coil out and have it tested.


CMOS

[AC94EXPLORER]

Originally Posted by CMOS

YOU can take the coil out and have it tested.


CMOS

thats what im gonna do

[AC94EXPLORER]

you have to use a voltage tester how do i find out the specs?

[AC94EXPLORER]

i found out i have a cracked head my spark plug on the passenger side back has bubbles and thats a sign of cracked head.

[CMOS]

"Has bubbles"? What does that mean? Please explain further.


CMOS

[AC94EXPLORER]

here check these out

http://i10.photobucket.com/albums/a1...xplorer001.jpg

http://i10.photobucket.com/albums/a1...xplorer002.jpg

http://i10.photobucket.com/albums/a1...xplorer003.jpg

http://i10.photobucket.com/albums/a1...xplorer004.jpg

[CMOS]

If that is the case then you should be able to confirm it with compression testing and a coolant system pressure test.

Keep us posted as to what happens...

CMOS

[AC94EXPLORER]

we did a pressure check and it holds pressure. the water is going through the exhaust. im gonna get both heads replaced for 1500. hopefully it will last me a few months.