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Hello, 

 

I just got done changing out the spark plugs and noticed that cylinders three and four are running extremely rich. My tuner suspects it to be a CAS issue or a coil pack problem, but my split fire coil packs are still pretty new. I’ll add a picture of the spark plugs. Has anyone else had an issue like this? 

1D0E4BB7-DA89-44AE-AEB1-78412773EDBE.jpeg

On 7/22/2021 at 8:56 PM, GTSBoy said:

Won't be CAS. Unlikely to be coilpacks. More likely to be injectors. Rich from problem injectors is nowhere near as common as lean from (dirty) injectors, but it does happen.

Are you all sure it's fuel and not oil?

I looked inside the wells and didn’t see any oil and each cylinder averages about 160psi when I did a compression test. 

Compression test is good, pretty much rules out rings etc

What sort of driving were you doing just prior to stopping and removing the plugs?  Can have an effect if you were idling or going very slow for some time.

Put some injector cleaner in your fuel tank.

If its still not right then take them out and get them cleaned [don't forget to number them].

If its still not right try new injectors.

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