Dead cylinder

[trent]

My 1999 Ranger 4.0 started acting up yesterday. The engine has a loud metallic tick when running and under any load it only runs on 5 with a distintive compressed air leaking sound on each rev. Compression test was good on all cylinders. Is this a problem with the lifters or cam, or might it be a valve not seating under load?
Thanks for the ideas!

 

[RonD]

'99 Ranger will have the 4.0l OHV

So could just be a bad lifter or push rod, cam would be a long shot

If compression is equal(within 10%) on all cylinders then not valves

Start engine cold, if it is misfiring, which you said it was, then shut it down.
Now pull all the spark plugs and find the WET one, thats the cylinder with the problem

Pull valve cover on that side to have a look

 

[trent]

Thanks a bunch, I will check it out!