Originally Posted by aceswerling
I know this is a bit of an old thread but I'm having the same lean AFRs on hot restart that the rest of you are describing.
I can see the WB O2 come online and then the AFRs hang out around 17 until they slowly converge to the expected value around stoich.
When I started troubleshooting this, it seemed reasonable to guess that the problem was caused by ASE not running long enough. I set my ASR taper the same as DMakinson suggested and the rest of my settings were pretty close already. I'm still seeing the problem even with the extended ASE times though.
Is this something we just have to live with because of the heat soak on the IAT sensor? In my case, MAT doesn't look that high in the beginning so I wouldn't expect the MS to lean things out because it's excessively hot. Also, I'm using the GM sensor that Rev sent along with my MS3 and that seems to be the one people like.
I'm attaching a small log file in case it'll help. Many thanks in advance...
your AIT is not heatsoaked, and your engine is already warmed.
your fueling simplly does not change based on the engine demands.
As you idle and it drops from 17AFR to ~14AFR but the PW remains roughly the same -- in the low 2.0ms range. Youre idling at the same VE table % 57.7 throughout the log and you only have about 5% fuel enrichments from warmup, which as they reduce you actually richen.
So at 1,400-1,300RPM, after the car starts, you're asking for the exact same amount of fuel as 850RPM later in the log.
and why is your spark advance so high? is there any reason why you're idling at more spark advance than the car demands at WOT? Something is telling the MS to add 5° of spark above the already ridiculously high spark table number.
why does your log show 100%TPS during cranking?
why is your battery voltage so low?
I don't believe ASE is your issue. You dont really need it when your car is already warmed up. and it only should last 2-3 seconds.
You richen up as your RPM better matches the fuel that your injecting. So either lower your cranking idle table and targets so the idle duty starts running the car at 850rpm or tune your fuel map so you actually have the fuel required when idling 1200-1400RPM. and then fix your spark while youre at it before you melt your pistons.