My 02 Ranger Edge 3.0 2wd has a really bad miss. It's not throwing any codes. The previous owner said that the Ford dealership did a compression check and cylinder 6 has no compression and that it needs valve work. I'm just wondering, before I go taking off heads and such, how likely is it that the valves are stuck compared to the piston rings being fried. I would think that if it was the rings, I would at least have some sort of compression. I could see where I would have no compression if the valves were stuck open though. Anyone know of an easy way to check this? Thanks.

 

I would say that if a valve was stuck open it is probably bent from being hit by the piston by now. Just guessing though, I've never been into a 3.0 to see how much space between pistons and valves. Pull the valve cover off and take a look.

 

Ok. Will do.

 

Do a wet compression test first that will tell you if its rings or a burnt valve.

 

Never go by a previous owner's diagnostics.
Do the comp test for yourself.

 

If the valve is stuck open you should also get some extra rocker noise since it will be rattling back and forth.

 

It is missing really bad. And will not go above 3k rpm. I don't hear any unusual noise though.