Trying to do a ltft tune on an 04' Colorado I-5. The problem is, after setting up a tune to force SD mode, the fuel system status is reporting "OPEN LOOP - NOT READY" even though I have closed loop switched to "OFF" in the scanner. It goes into Open Loop without a problem when under WOT, however. Any suggestions on what I have done wrong? I have the perameters set the same way on the SD tune file for my 07' Colorado I-4 and I don't have this issue with mine.
Anyone?
The only other issue I'm having seems to stem from the same source. When OL - Accel/Decel becomes active, the PCM seems to ignore the commanded AFR (set to enrich to no more than 11.8) and drop to as much as 10.10. Any ideas why that is happening?
I think I figured out the overfueling problem, it is possible it is going into COT enrichment. Haven't had a chane to test that out yet, but it makes sense.
Still at a loss at why I can't lock it into Open Loop.
What exactly did you do to force SD mode?
Bill Winters
Former owner/builder/tuner of the FarmVette
Out of the LSx tuning game
Same thing I do with mine. Under "VCM Controls" in the scanner program, "Fuel and Spark" tab, I turned Closed Loop to "OFF". When i do that, "Fuel System Status changes from CL - Normal to OL - Not Ready, and I am stuck right there.Originally Posted by 5_Liter_Eater
I prepped the tune file by disabling DFCO, disabling PE and copying spark tables to match, Set MAF Fail to 0.
Last edited by swedluap; 04-15-2008 at 03:46 PM.
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