Well, I've started setting up and tuning the 60's in my car. I have my PE tables to set an 11.6:1 afr.....but it kept showing commanded down into the 10's.......couldnt figure it out while I was driving around. Got home and noticed I didn't set my COT overtemp values to 0......would this cause the over rich commanded AFR on WOT??? Thanks
based on the values in your tune, your cot will add anywhere from .06 to .18 to your commanded pe fueling calc, depending on the cot temp. threshold.
so in your case where your desired pe ratio is 1.269 (11.6), once cot activates, your pe ratio becomes anywhere from 1.329 to 1.449 (11.0-10.1).
if you log the cot status bit you can see when cot activates.
are you trying to calibrate using your wideband sensor and afr error % pid??
if so, I can see a couple problems.
you are still running in closed loop with both ltft and stft enabled.
a few of your eq ratio adder tables are still enabled, as well as dfco and cot, which all can complicate the fueling calcs while you are trying to calibrate things.
Last edited by my_bd; 02-23-2008 at 11:29 AM.
my_bd 2004 Saturn Ion Redline - 2.0L Supercharged LSJ (P12) 13.1 @ 110
ok, then I suppose the COT was my problem like I thought. Yes, I am using my wideband sensor to calibrate. However that scan I posted I wasn't attempting to calibrate anything, just a quick pull so I could post it up. When I was adjusting the fuel I had the car set up in open loop, and the DFCO turned off, I guess I just "forgot" to disable the COT.
At least I know where my stupid 10.0:1 afr was coming from hahaha
I would recommend adjusting MAF/VE with PE/DFCO/COT disabled and forced closed loop to get the magic 14.7 average AFR. Then you can re-enable PE and such and dial it to the desired WOT AFR, then use the wideband to verify or tweak from there.
All these corrections for PE doing wideband tuning to get base MAF/VE right is jumping through hoops to get to the ground your standing on already, if you get my drift.
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