PE issues: cant lean out in PE
08-11-2007, 03:46 AM
#1
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PE issues: cant lean out in PE After scaling the IFR table for 55lb injectors, the car is still running rich in WOT and getting the PE table as low as 1.035 still has a 11.7-12:1 AFR. LTFT's are -3,-4 and it locks -.8 in WOT. Stoic is easily maintained. Good starts, no surging, bucking, hunting for idle. If it wasnt for the rich condition, I would say it was a great tune.
Its a 6 liter C6 corvette with a 403 stroker. 236 cam etp225 heads. Static compression is 11:1.
Its a 6 liter C6 corvette with a 403 stroker. 236 cam etp225 heads. Static compression is 11:1.
08-11-2007, 11:31 AM
#3
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Originally Posted by wait4me
WOT is effected by MAf table, Ve table, Injector flow rate, and pe vs rpm. It will command the richer value of them. But if it is that a/f, i would suggest turning off Cat over temp protection and then seeing what the af went to.
08-11-2007, 01:23 PM
#5
Your IFR table is off, the numbers are too small .... could be a bad calculation or your rail pressure maybe higher than you think. Increasing your IFR table will push trims in a positive direction but will get control of your WOT back...
Alternately you can tune your VE and MAF and use PE for commanded (or even tune just the bottom of the VE table and calibrate the MAF against the VE.
Any of these should work
Alternately you can tune your VE and MAF and use PE for commanded (or even tune just the bottom of the VE table and calibrate the MAF against the VE.
Any of these should work
08-11-2007, 01:45 PM
#6
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I have seen this happen as well on the dyno with a C6. No matter what changes I made to the PE table, it would not lean out. In the end, I scaled the high end of the MAF table to adjust the WOT AFR and that worked.
08-11-2007, 02:40 PM
#7
Originally Posted by VinceTrifecta
I have seen this happen as well on the dyno with a C6. No matter what changes I made to the PE table, it would not lean out. In the end, I scaled the high end of the MAF table to adjust the WOT AFR and that worked.
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08-11-2007, 02:48 PM
#8
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No, it was completely stock except for headers, high flow exhaust, and cold air intake.
It was *definitely* being stubborn. ;-) I tried scaling down the PE tables as much as 10% without *any* change to the WOT AFR. In the end I put the PE tables back to stock and just adjusted with the MAF calibration table.
I've tuned a few other LS2s but never saw that happen before (e.g. the other cars I tuned responded to PE table changes predictably).
It was *definitely* being stubborn. ;-) I tried scaling down the PE tables as much as 10% without *any* change to the WOT AFR. In the end I put the PE tables back to stock and just adjusted with the MAF calibration table.
I've tuned a few other LS2s but never saw that happen before (e.g. the other cars I tuned responded to PE table changes predictably).
08-11-2007, 03:15 PM
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Like Jesse was saying (or trying to say...looks like it was left out):
WOT will take the richer commanded value between PE vs RPM and the Open Loop Fuel Air tables. In EFI Live, they're PE Modifier Based on RPM and Commanded Fuel in Open Loop Normal....found in the Fuel>Mixture folder.
If you're leaning out PE and the commanded AFR is not changing, check the OLFA table.
WOT will take the richer commanded value between PE vs RPM and the Open Loop Fuel Air tables. In EFI Live, they're PE Modifier Based on RPM and Commanded Fuel in Open Loop Normal....found in the Fuel>Mixture folder.
If you're leaning out PE and the commanded AFR is not changing, check the OLFA table.
08-11-2007, 03:57 PM
#10
Originally Posted by SSpdDmon
Like Jesse was saying (or trying to say...looks like it was left out):
WOT will take the richer commanded value between PE vs RPM and the Open Loop Fuel Air tables. In EFI Live, they're PE Modifier Based on RPM and Commanded Fuel in Open Loop Normal....found in the Fuel>Mixture folder.
If you're leaning out PE and the commanded AFR is not changing, check the OLFA table.
WOT will take the richer commanded value between PE vs RPM and the Open Loop Fuel Air tables. In EFI Live, they're PE Modifier Based on RPM and Commanded Fuel in Open Loop Normal....found in the Fuel>Mixture folder.
If you're leaning out PE and the commanded AFR is not changing, check the OLFA table.
AFAIK for F-bodies the richest commanded in the OLFA is 1.13 AT OPERATING TEMP, so if your PE figure needs to be smaller then..... yeah
08-12-2007, 12:14 AM
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Hey guys its my car we are working on. For giggles I put the PE down to .95 and it went to 12.3 but I think something is goofy. I'll read what you wrote a dozen times and see what I can do tomorrow. Its HP.
On a side note, I could be cruzing along at 1700rpm and all of a sudden the car will start bucking slightly and the AF shoots to 16:1. It will stay there till I blip the throttle. Its almost as if the thing goes into WOT mode but it gets lean. Related, or seperate gremlin? I looked at the scan and none of the sensors hard fail or anything, the O2s kinda peg while it does this. It happens like once an hour at best.
On a side note, I could be cruzing along at 1700rpm and all of a sudden the car will start bucking slightly and the AF shoots to 16:1. It will stay there till I blip the throttle. Its almost as if the thing goes into WOT mode but it gets lean. Related, or seperate gremlin? I looked at the scan and none of the sensors hard fail or anything, the O2s kinda peg while it does this. It happens like once an hour at best.
