dead cylinder

[wv explorer]

I have a 94 Explorer 4.0 automatic with around 160000 on the second motor. It recently developed a miss that we can't seem to pin down. We checked plug wire, put in a new plug, checked coil pack, injector, did a scan, all ok. From there did compression check, it was fine. Pulled valve cover to check rocker arm and push rod,they were ok. What am I for getting to do? Thanks in advance for any help.

 

[corkey]

try pulling off the coilpack wires one at a time till you find the bad one, ,
and if yu did all that stuff and the miss stayed around, i would say it is either a wire or the coilpack,

 

[wv explorer]

Thanks Corey we tried that. I believe it's cylinder # 5 that's the culprit.

 

[KobeJ05]

i have oil on my spark plug from cylinder 4. does that mean its a worn ring? wv explorer did you have any oil on the plugs?

 

[MrShorty]

Thanks Corey we tried that. I believe it's cylinder # 5 that's the culprit.

Problems with cylinder #5 have sometimes been associated with a loose/leaking lower intake manifold gasket. Was the #5 spark plug fouled? In any case, because of this association, I'd probably try tightening the lower intake manifold gasket (this often gets discussed in conjunction with a "pinging" engine) and see if that resolves the issue.