Weird problem with airflow spike causing temp power failure

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August 25th, 2008
ringram

Weird problem with airflow spike causing temp power failure

This has happened a few times, but as I wasnt logging at the time couldnt get to the bottom of it. I have messed around with Torque management and ETC airflow Diagnostic settings and I think its somewhat better.

No MIL or DTC's are set but going over the log this am I found g/cyl spiked to 1.46g/cyl! which is well into FI territory and Im still setup stock NA. You can see the spike on the "79200" vertical bar. Fueling doubles which might be what the power loss is all about. Too rich to burn properly? Question is how to stop the spike? MAP is ok, which means airflow calc in SD should still be ok. VE looks all nice a smooth. RPM is reported ok etc.

http://img33.picoodle.com/data/img33...sm_1fd6cfb.jpg

Does anyone have any thoughts on the matter?
August 25th, 2008
GMPX

Mafless?
August 25th, 2008
ringram

Sorry yes, CLSD no LTFT's Stock LS2 with OTRCAI + RollerRockers

Its at the end of this logfile http://www.systemsup2.plus.com/BBL00010.zip
August 25th, 2008
GMPX

ok, simple fix.
Open Virtual VE table, select entire table, add '1' to all cells.
Generate coeffs, save file, flash.
Le us know how it goes.

Cheers,
Ross
August 25th, 2008
ringram

I did think maybe something was weird in there and was going to hit the smooth button, but adding 1 all over sounds better. Ill give it a bash and report back.
September 5th, 2008
Redline Motorsports

What happened with this?
September 6th, 2008
Delco

Ther is a bug in the GM code that shoots to a incorrect zone , by adding 1 to every value in the VVE table EFILIVE recalculates the coefficients and corrects the bug.
September 7th, 2008
ringram

Yeah, one to watch out for :)
So far so good, its not done it again, but you have to hit the right cell for it to trigger.

As discussed I added 1 to all cells and recalculated values.
April 15th, 2009
ls1vt209

Has anyone had this happen and seen the car go lean?

Reason I ask, a mate of mine who has a VE has seen the AFR's go lean without any change to the tune.

Cheers
LS1VT209
April 15th, 2009
Delco

Quote:

Originally Posted by ls1vt209

Has anyone had this happen and seen the car go lean?

Reason I ask, a mate of mine who has a VE has seen the AFR's go lean without any change to the tune.

Cheers
LS1VT209

If you encounter the bug the injectors shut off completely and go very lean for a instant , the cure is easy , add 1 to the whole VE table and recalculate the co efficients.
Only occurs mafless when there isnt a change to every zone