Okay my buddy's civic is throwing a CEL-73 cylinder misfire on #3. Car Idles rough and when you pull the plug on #3 nothing changes. So we do a tune up(it's due for one anyway). Plugs, wires, cap ,rotor, etc. Still a rough idle. So I do a compression test on #3 and #2(just for comparison). #2 = 196 p.s.i. / #3 = 5 p.s.i. (that's right 5psi). So I'm guessing bent or stuck open valve or completely shot rings. So it's time to pull the head, right?? Find out what it is........I'm just double checking to make sure I'm not forgetting anything. Thanks.

 

bump...just making sure I'm not missing anything...

 

Yea if his getting no compression at all in that cylinder something took a **** on him. Gotta pull the head to find out.

 

Thanks for the reply.....I'm thinking it is one of the valves, cause even with really bad piston rings I thinkyou should get better than 5 p.s.i. in the cylinder