overrun fuel cut is driving me nuts
#1
overrun fuel cut is driving me nuts
No matter what I do, I always get lean spots between shifts. Seems overrun fuel cut kicks in almost instantly (PW drops with TP) although it's turned off. My AFR calibration doesn't go leaner than 19.5 BTW.
Weird thing is that PW / dutycycle don't drop entirely to zero, suggesting it's not overrun fuel cut? Is there some other setting that I'm overlooking?
Autotune always leans out the bottom row, but adding fuel there, doens't make a difference.
Weird thing is that PW / dutycycle don't drop entirely to zero, suggesting it's not overrun fuel cut? Is there some other setting that I'm overlooking?
Autotune always leans out the bottom row, but adding fuel there, doens't make a difference.
Last edited by WestfieldMX5; 07-02-2010 at 01:32 PM.
#13
Well, it's not overrun. Switched on overrun and duty drops to zero.
So it must be something else. My bottom fuel row is only 2 points leaner than my idle row. Autotune always leanes it out to 30ish, but raising it to where it is now does not seem to make a difference. I'll try raising more.
So it must be something else. My bottom fuel row is only 2 points leaner than my idle row. Autotune always leanes it out to 30ish, but raising it to where it is now does not seem to make a difference. I'll try raising more.
#14
That is strange. Are you sure it's leaning out and not dumping too much fuel? It drops to full rich and then goes lean. Your cells are 2/3 the fuel they are at 60kpa. That sounds like a ton of fuel to me. Increase it more and I'd bet you'd start getting backfires. What does your timing map look like? When autotune leans it out to 30, does it run the same?
Last edited by TrickerZ; 07-04-2010 at 09:12 AM.
#20
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it is odd that your PW goes to 1.2 and isn't completely cutting. what would happen if you added 10 points to your 20kPa row on your VE fuel table? My logs look similar, but the leanness doesn't kick in right away, think it's cause my lowest kPa row in my VE table isn't so leaned out like yours...it hovers at 1.3PW, fully lean, and then kicks off completely with overrun.
Have you tried using EAE? Looks like you're really not getting much reacting from the TPSdot, dunno why you arent using EAE, should really help improve the AE between shifts.
Have you tried using EAE? Looks like you're really not getting much reacting from the TPSdot, dunno why you arent using EAE, should really help improve the AE between shifts.