P0301 Ford Escape

Hello, I have a 2010 Ford Escape with about 237k on it. Keep getting a misfire cyl 1. Replaced spark plugs, swapped coils to different cylinder locations, removed injectors, cleaned and swapped injector 1&4. Still only P0301. Ran compression test and on cyl 1 and cyl 3 getting 150. Cyl 2 and cyl 4 close to 175. No vacuum leaks detected. What are your suggestions to where to start from there? It’s a 2.5L

Have you performed a leak down test??

Also does mode 6 agree with the code? Try pressurizing the cooling system check for coolant in the cylinder after a few hours?

Have not preformed a leak down test yet, have read you can have a bad valve with good compression is that true?

Are we checking for a pulsing ground when doing this?

So I did the old paper trick with the exhaust, and found it sucking it in ad blowing it out. Is this test very accurate for a valve issue?

FordGuy1990 wrote: Have not preformed a leak down test yet, have read you can have a bad valve with good compression is that true?

Some valve related problems won't show up on a compression test or a leakdown test. That said a leakdown test does stand a good chance of finding why your suspect cylinder is ~25 psi low.

What kind of misfire do you have? A dead miss or something less severe? And is it constant or intermittent?

Monde wrote: Thank you Matt, for pointing out the lower compression issue. I didn't read the original post through and missed that. Shame on me.

I was just replying to the OP. And he did say two cylinders were lower, but not really bad, so don't beat yourself up about "missing it".

Like others have suggested, I'd definitely do a leakdown test. At least on #1, preferably on all four. Burned exhaust valves are common on this engine at higher mileages.

Here’s what the piston looks like, not sure if that’s the valve or a part made into the piston? Any ideas, the piston is clean expect where those to pieces are

Seems to be intermittent, sometimes it’ll idle rough others it’ll idle like new, but regardless of the idle when you get around 50-55 you’ll get a vibaration.