iv been ve tuning for awhile now and i cannot figure out how to not have a lean idle on first start.does not matter how hot the engine is when it starts.it runs lean for up to 20 sec. im running 42lb bosch injectors on a cammed ls1.let me know what im doing wrong in my tuning and scanning.iv been applying all changes to my main ve tables.also some times when it runs lean at idle my scanner will say its running rich by indicating green cell hits.
Speed density aka VE is not accurate at cold engine temps from what I've seen.
What I've done is if I'm targeting a 13.5:1 AFR during cold start/warm up I would have to command a much richer AFR like 12:1 in the open loop EQ ratio table at the lower coolant temps.
Interestingly enough this only seems to happen in speed density mode, once MAF is enabled the commanded AFR is accurate at cold start.
Have you been wideband tuning with your short term fuel trims active?
Make sure to smooth the VE out when making changes, you have way too many spikes in it.
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.
Yes on tuning with stft active.Whats the best way to smooth ve table?
And what would i need to change to make 100% sure my inectors are firing correctly so i can rule them out while tuning.
the fuel trims make corrections and negate the reported error of the wideband as the ecu has already masked the true error.
keep reading the wideband and disable ltft and stft. then the true error will be reported on the wideband.
2000 Ford Mustang - Top Sportsman
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