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"Fuel Trim In Use LTFT" causing Rich AFRs part throttle?
I've been chasing some rich issues on part throttle, and it seems that "Fuel Trim In Use LTFT" kicks on at open loop and causes my AFR's to go pig rich, and even cause rich knock. What exactly is Fuel Trim In Use? my cruise trim is ~7%, yet fuel trim in use is 17%. What do i need to adjust to bring this number down and correct part throttle AFRs?
I went through most of that thread but they don’t seem to talk about “fuel trim in use”. I reflashed my rom to reset trims. Went on a 30 minute cruise, then idled for 30 minutes. My LTFT low is .69 and my LTFT mid is 2.9 I believe. I don’t know what else it could be
Fuel pressure at idle will be too high, makes AFR too rich, causes trims to drop in order to lean out the AFR at idle to get it closer to lambda 1.
It's probably programmed too rich too. I would have expected AFRs in the 12s there, not 10s.
What about the smoking engine?
Did it affect the o2 sensor?
What about the NBo2 sensor?You didn't log it.
Last edited by RightSaid fred; Mar 23, 2018 at 07:52 PM.
