Misfire

[nebraskamonte]

Went out to start the turbo Monte as i do every couple of weeks. Only this time it was missing pretty bad. Constant misfire that seems worse under load. I have taken no action yet as I'm a dealer tech and time off is valuable. I'm bringing it to the shop tomorrow to dig around and see whats happening. Any guidance would be appreciated. I will update tomorrow on what i find.

 

[nebraskamonte]

Ended up getting pretty sick so i wasn't able to touch it until today. checked manifold temp and #5 was only at 91 degrees. pulled the plug and it was black. dead misfire on cylinder 5. I checked the plug wire and the crimp was not the greatest. re crimped the wire, tried it, misfire is still present. There is spark to the plug when grounded. I was running the ngk plugs that were recommended on the before black website. Any help is appreciated.

 

[nebraskamonte]

compression was 131 on cylinder #5.

 

[ek02]

Leaking injector causing black plug and low compression due to the oil washing off the rings on 5? If the other cylinders are 150 or so it won't cause a dead miss under load, but a fuel fouled plug will. Maybe swap injector to another cylinder and see if the miss follows it. That's assuming it is injected.

 

[nebraskamonte]

It is carbed, I ended up replacing the plug with a delco and checked out the crimp on the wire, it appears it was never properly crimped. i re-crimped it and threw it all back together and she ran fine..I'm guessing it was the wire. Thanks for the help though. Wish i had the money to go sfi.

 

[turbo nasty]

Bad wire fouled the plug