Still trying to figure out idle fuel
#1
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Gents,
I really need some help here. I'm still trying to figure out why my idle AFR is so rich at startup. Idle VE is OFF. WUE is 100% straight across. I don't need added fuel when she's cold. AFRs start out in the low 11s.
The car was relatively warm when I started this log. At the beginning, EGO is pulling a lot of fuel (20%) and she's at 13.7. At 41 secs, the CLT crosses 170 degrees and EGO goes from 80% to 100%. I have no idea why. Duty Cycle goes from 1.7 to 2.0 at roughly the same time. Then over the next 20 secs EGO starts using the full 20% Authority I've given it. At around 60 secs, it happens again. EGO jumps from 80.7 to 100% and Duty Cycle goes from 1.7 to 2.0. It takes 10 seconds for the full 20% EGO to kick in, and the AFR climbs to the high 13s. At 80 secs it happens again. So, it happens at ~40, 60, and 80 seconds. WTF?
At 85 seconds, I blip the throttle. When the idle settles out, the AFR is at 14.7 with EGO at ~102%. For the next five minutes, the AFR stays at around 14.7 with EGO adding just a bit of fuel. The Duty Cycle bounces between 1.4 and 1.5.
Any advice would be greatly appreciated.
I really need some help here. I'm still trying to figure out why my idle AFR is so rich at startup. Idle VE is OFF. WUE is 100% straight across. I don't need added fuel when she's cold. AFRs start out in the low 11s.
The car was relatively warm when I started this log. At the beginning, EGO is pulling a lot of fuel (20%) and she's at 13.7. At 41 secs, the CLT crosses 170 degrees and EGO goes from 80% to 100%. I have no idea why. Duty Cycle goes from 1.7 to 2.0 at roughly the same time. Then over the next 20 secs EGO starts using the full 20% Authority I've given it. At around 60 secs, it happens again. EGO jumps from 80.7 to 100% and Duty Cycle goes from 1.7 to 2.0. It takes 10 seconds for the full 20% EGO to kick in, and the AFR climbs to the high 13s. At 80 secs it happens again. So, it happens at ~40, 60, and 80 seconds. WTF?
At 85 seconds, I blip the throttle. When the idle settles out, the AFR is at 14.7 with EGO at ~102%. For the next five minutes, the AFR stays at around 14.7 with EGO adding just a bit of fuel. The Duty Cycle bounces between 1.4 and 1.5.
Any advice would be greatly appreciated.
#2
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I'm also relatively new to megasquirt tuning so I'm sure I'll get corrected, but if WUE is 100% across the board then it's not doing anything, and your ASE is only at 11% max for cold starts so if you're rich at startup then the issue should be mainly with the idle cells in your VE table, unless your req_fuel is incorrect. Not sure what you mean by VE Table being "Off" unless you're on MS3 and there's an option to not use the separate idle VE table? Dunno, like I said, not an expert. But if it were my car I'd start with a basic WUE curve like the basemaps all come with and pull a little fuel from your idle VE cells. or as the experts around here would say, "try tuning the car."
#3
Cpt. Slow
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Usually when EGO jump from a correction factor to 100% (no correction), it means EGO was disabled for some reason. Looking at your EGO enabling parameters, I don't know why though. AFR stayed between 10 and 19, load stayed above 20, etc.
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