I tried to find a way to modify cold idle AFR but realized the same cells are being used while cruising and there the AFR error is almost zero. After cold start in these same cells it is requiring a lot more fuel. This might be a false thought, I assume the narrow bands do not know the actual AFR and the end result is an idle which moves from 1500 rpm to 300 rpm.
If I let it idle, it will run ok after a while. It idles fine after starts when the engine is warm. This is hard to replicate since the engine warms up so quickly, I can only get 2-3 attempts to log this and then it idles fine.
Here is the log attached. And the tune of course.
The engine is LSX 431cid with Smog2 cam, longtubes, MSD Atomic intake, no MAF. This passes the sniffer test when warm so the only problem is the bad idle when cold.
Bit more of a challenge this one as I presume you'll need to have all the cat lightoff stuff still enabled? If no, then modify my tune and delete it all.
Didn't notice your widebands changing. Better to log with commanded EQ if logging widebands as lambda.
Thanks, I copied the changes and I will test when I can.
The wideband was not attached to the HPtuners while I took the log file. There are cats, so the COT must stay.
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