Ford Repair: 05 escape 2.3 engine, cam lobes, liter engines

Question
I am working on an '05 Escape with a 2.3 engine. Developed a miss recently,(yet passed an e-test!) Compression in #1,2,& 3 are all good but #4 is half. No fluids are leaking or being exchanged between cylinders,doesn't leak oil or have blow by, injector ciruit lights up noid light, coil has been tested & swapped with another just to be sure, cam lobes look alike, no obvious wear to that cylinders lobes. When shop air is put to cylinder it goes out the tailpipe, am I looking at bad valves already? Less than 100,000km, other 3 cylinders are VERY strong, and no blow by has left me thinking valves but curious as to why just #4 cylinder. Am I missing something?

Answer
Hey there, we dont usualy see too many engine problems with these 2.3 liter engines, But all the tests that you have performed are good and valid to check your problems. WIth a burnt valve the only thing i can think of is the type of fuel ou may be using, You will have to pull the head off to verify the actual concern Do that and let me know what you can find.
gppd luck
Chris P