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ForcedC5
January 5th, 2013, 08:00 AM
Hey and Happy 2013 to Everyone...

I've decided to pick up an LS3 MAF coming from the original LS1 MAF and started logging to get things calibrated. Got it to run pretty decent but when I apply numbers from steady-state driving, the same cells when coming from a stop, accellerating in 2nd or 3rd, get really lean (AFR's of 16+). It's lean for sure cause it starts stumbling and being rough.

So, I correct the MAF to get that back in line but now when going back to steady-state over those same cells, they show rich or BEN's of .95.

I'm using the normal BEN filters... Is there something else that could be causing this or is there a better way to log for the MAF?


TIA,
Arnel

joecar
January 5th, 2013, 10:56 AM
Post logs.

ForcedC5
January 5th, 2013, 06:27 PM
14340

Here's a log w/ a few stop and go's before getting steady...

ForcedC5
January 7th, 2013, 10:16 AM
Fyi, a few things I tried since the last post:

I tried to confirm I was not referencing the VE by zeroing out the VE and setting B0120 to 0. The car started but would die after a second or so... further attempts would basically have the motor just die more immediately. Put the old VE back and left B0120 at 0 and it starts/runs as it did prior.

I tried filtering out any/all decels w/ no significant difference....

Confirmed MAP # at key on was good.

joecar
January 7th, 2013, 04:11 PM
Your wideband shows too much variation to be able to make a correcting map.

ForcedC5
January 7th, 2013, 06:32 PM
Thanks Joe... Yeah... I suspected the WB as possibly being bad and actually borrowed a buddy's WB to isolate it and confirm. Just got lazy and hadn't gotten to the point of putting it in to test.

I have a feeling it's reading a point leaner then actual, with 13.5 really being 14.5, and my maps being pretty way off/screwed. At least that's what it showed with the trims on and the gauge showing 13.5-13.8.

I'll do a free-air calibration real quick and probably just get that other sensor in there just to make sure.