What would cause the O2 voltage to get stuck dead lean or rich? Attached in the logs is a drive file where certain points the O2s get stuck lean or rich for a few seconds then return to normal. I checked other parts at the same rpm and MAF Hz and the O2s are reading correctly. Anyone see something like this before? TIA
Hard to say if it's a cat test because you are not logging the commanded AFR.
And it's not smart to disable all your sensor 1 o2 codes. You will have no idea if you are having an issue with the upstream o2 sensors if everything is turned off.
If it is a cat test the commanded AFR will change from stoich to 16 AFR and 13 AFR at random. Normally the fix is putting the rear o2 sensors back in the harness and tie them out of the way, they don't need to be in the exhaust.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
Someone else had previously tuned this truck and I didn't even think to look at the front O2 sensor DTCs being disabled. I guess they did that when they decided to run it in open loop also. Thanks for the input 5FDP!
Reply With Quote