Post current tune file and a log from it.
If you're seeing KR then:
- make sure MAF and/or VE is correct at that operating point (not under-reporting).
- make sure you're commanding sufficient fuel (if low load, OL look at B3605 or B3647; if high load, make sure PE enables and commands sufficiently rich).
- make sure you're not commanding too much timing at high load.
- make sure oil is not being ingested via PCV system.
- make sure your fuel is octane 91 or higher.
- make sure your intake air is not getting heated.
- make sure coolant is not overheating.
What spark plugs are you running...?
If you're running boost, you have to make sure VE is good, and that you add fuel and remove timing (COS has tables for this).
Thank you again. I am realizing a lot of things and it shows on the truck, my map is still rich at the end 12 afr and bit rich on the bottom 13.7 when idling, once the a/c kicks in goes to 14.7afr. Appreciate your time! will clean up few things and record. I was upgrading few other things on the truck (: roof rack,LED lights( 2003 Tahoe, garret TP38 turbo, large after cooler 4 inch, TR6, 48 lb fuel injector, the green backs, 5.3 l ls is running great. i am sure the knock is still from incorrect afr map after 3 psi. Goes rich to 12 Will work on it this week and get back
Assuming your wideband indicates the same as commanded fueling (i.e. VE and MAF are reasonably correct)...
when running NA at WOT, you want:
- commanded AFR to be about 12.6,
- commanded spark to be no more than 24* (i.e. total timing).
when running boost at WOT, you want:
- commanded AFR to be about 11.5,
- commanded spark to be no more than 14* (i.e. total timing).