Ok Thanks guys. So when adjusting my openloop idle for a cam I should have been working in the AFR table and not the BLM table?
Ok Thanks guys. So when adjusting my openloop idle for a cam I should have been working in the AFR table and not the BLM table?
No, use the BLM table. This fixes the data the ECU is using to calculate the engine airflow.
Open loop idle looks at the VE table for fuel and seems like it refers to the O2 voltage very little, if any. I'm not sure about a wideband, but a narrowband will look lean at an idle when it is NOT lean. This is because of the increased overlap of a bigger cam compared to the factory.Originally Posted by Scorp1us
What I did to nail my idle, was enable closed loop idle fueling, then bump my o2 voltages down .025v at a time, drive around the block, let it idle and see how it felt, then repeat until I had it idling the smoothest. Adjusted the VE table until the BLM was 128 at an idle, then finally, disable closed loop idle fueling again. My 454 idles the smoothest with the Lean voltage at .300, the mean voltage at .350, and the rich voltage at .400 with the baby cam. I could probably narrow up that swing a little bit, but I have cats in my truck.
94 Blazer, Turbo'd 350 TBI - DD
1991 2500 Suburban Adventure truck - 4wd conversion, 4-link F/R, 582ci CNP Big Block with Terminator X EFI backed by a 6L90 and twin stick'd NP205 t-case
2012 Porsche Panamera Turbo - Date night car :)
1979 16' Action Marine/"Johnny Cash" Merc Bridgeport Champ Motor - Metalflake Maniac
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