I have pictured 2 different sets of plugs pulled from my boosted 500whp GSR running on e85. As you can see cylinder #1 has repeatedly fouled.

I have already moved the fuel injector to #2 with new plugs and the the bad plug remained #1.

compression test results were 205 psi across the board.

Does anybody know what is causing this?

Thanks, Doug

 

Does your ems have individual fuel trims for each cylinder? If the trim is off on cyl1 then that would explain the constant fouling. Did you relocate the bad plug to another cylinder or put a fresh set in after moving the injector?

The only other options are a wiring issue or the injector drivers in the ecu are acting up

 

Car is tuned with Crome but I am unaware whether trims are adjusted individually. Would e85 cause a plug to foul out black?

I did install new plugs when I moved injector.

 

Looks like could be a little oil. If you moved injector around and it's still on same cylinder it's a wiring issue or oil issue. Pull manifolds off see in valve seals are leaking. Are you running stock PCV ?

 

I was suspecting a valve seal. I have a breather and catch can. Only the 2 "oil drain ports" on the back of the block and the small port above the plugged off port go to the catch can. How can I test for a bad valve seal?

 

You can't. But while the car sits the seal will keep leaking to a point. So it will be easy to see

 

That's how I've always determined a bad valve seal but my car doesn't smoke at all that I can see. I'm suspecting that the leaking may only be occurring during high load high boost situations and I'm not paying attention behind me when I'm foot to the floor haha.

Possible?