Fuel trims are way off from one bank to the other

This is my first time posting to the forum. I have a 1999 k2500 suburban that has been 0411 swapped and a roadrunner installed. The engine is a BBC 427 with aluminum Pro Topline heads and a Comp 11-772-8 camshaft. The intake is a dominator style with a holley efi 90 degree elbow and 110mm ls1 style tb, the injectors are boesch 42lb/hr, and since this is a gen iv engine im using an msd hall effect crank trigger on the damper. I have suddenly developed a problem where the fuel trims long term and short term are seriously off, Bank one will some times show more than +25 while bank two will show around -8. I had a leaking intake gasket and was thinking this was the cause i replaced the intake gaskets with no real change, also i have checked the exhaust over and cannot locate any kind of leak in the system. One question that kees coming to mind is that since its a mechanical roller cam could valve lash cause this? I will include the last log i made and a copy of the tune. Any help or advice is greatly appreciated im beating my head against the wall

I'll look at your files.

Are there any airleaks in the exhaust after the NBO2 sensors (say up to 12 inches past)...?

Also, did you check for leaky injectors...?

Also, did you check for air leaks at the injectors, and between the MAF and intake manifold...?

( Hi Madman13, I deleted your duplicate posts, the forum was marking them as unapproved, I'm not sure why. )

The exhaust is solid past the o2s and the wbo2 is mounted within 2 inches of the NB on the drivers side, i have pressure tested the injectors and they didnt bleed off, i did do the old school wd-40 around the injectors while running and no change as well. Ill check the MAF boot tomarrow but i wouldnt thnk it would affect just one bank so much. Thanks for helping with the duplicate posts too i kept posting and they kept disappearing

Swap the injectors bank to bank. If the high trims follow the injectors, then it's an injector problem. If the high trims stay on the same bank, then it's an airflow problem.

Quote:

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Originally Posted by statesman

Swap the injectors bank to bank. If the high trims follow the injectors, then it's an injector problem. If the high trims stay on the same bank, then it's an airflow problem.

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^ this is a great diagnostic, thanks :cheers:

over the weekend i swapped out the injectors for another set i had in the shop and boom the fuel trims fell back in line. Thanks for all the hel

Glad you got the injectors sorted out.