Look over the short fuel trims, and lets hear some theories.

injector stuck open on cyl 5? hard to read that graph..

Left side of the graph is "subtracting" fuel, right side is adding.

i gotta ask is there any kind of power loss with this odd increased fueling of Cyl 5

Customer brought in his truck for a check engine light. This will give you an idea about the nonsense that we go through to repair something like this. Performed KOEO, found codes P0275 and P0305 (both related to cyl #5). Pinpoint tests have you test fuel pressure, fuel quality, then compression tests. Then you test resistance at the 15 pin connector at the front of the head. Resistance was ok. Had to get "prior approval" for an injector replacement. They asked for more tests. Relative compression, fuel debris tests by removing #1 and #2 injector lines and fastening rubber hoses to them and directing fuel flow while cranking into a coffee filter. Because those two lines were removed, they have to be replaced. Finally, approval came through. All day to replace 1 injector.

nflfreak43 said:

i gotta ask is there any kind of power loss with this odd increased fueling of Cyl 5

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No apparent power loss. He just had a check engine light. Specs say normal until -/+ 20

so what was the conclusion? cyl 5 injector was bad?

nflfreak43 said:

so what was the conclusion? cyl 5 injector was bad?

Click to expand...

Yep, just replace #5, reset fuel perameters, clear codes, release to customer.

thats what i said the first time... ugh.. you had me thinking i was freaking wrong...

OK, what would happen if you don't repair it?

wouldnt it leakdown into the oil, cause oiling issues and eventually lead to catostrophic failure.

nflfreak43 said:

wouldnt it leakdown into the oil, cause oiling issues and eventually lead to catostrophic failure.

Click to expand...

Burning up a piston and cylinder too.

that too.... its all an extension of one another..

Anyhoo, thats a taste of whats ahead for you!

yep... cant wait....