Hi, i recently picked up a 96 xj 4.0 that had a pretty good misfire. I started replacing the basics (spark plugs, plug wires, distributor) but none of that helped. Today i ran a compression test an the results are as follows
1-150+
2-150+
3-70
4-70
5-150+
6-150+
I noticed that when i was testing cylinder three i could hear the compression leaking from 3 into 4. I put a sparkplug in cyl 4 to see if the noise went away, and sure enough it did. I dont have milky oil or bubbles in the coolant, nor does it use any coolant. Could it still be a blown head gasket? The jeep has the 0630 head which is pretty rare to have crack. Is it possible that my head cracked? Anyway im going to pull the head tommorow and find out.

 

Well what did you find?

 

Didnt get the head off yet, i got the manifolds and p/s A/C pumps off, have some rusty head studs that i lubed up hopefully they'll come out tommorow.