Quote:
Originally Posted by freerunner
That would only make sense to me if the iat compensation table exaggerates in its current form. Else the ecu should add fuel to compensate for higher air density, if it's cold.
Nevertheless, comparing the actual log to an older one with similar ambient temps (where ltft was zero nearly all the time), I'm pretty much certain that adding the 70% pfi at low loads exposed the pi<>di proportion is off.
I didn't care about going full di when I calibrated the maf scale back then. :-/
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Interesting. Perhaps fuel quality may have something to say about this as well.
I'd like to know how much difference your PI will end up compared to a maf scale dialed to 20*c (68*F) in full DI where the IAT compensation is 0 on the stock temp compensation table for the entire range. That's if you want to be as anal as I am with this thing. My previous MAF scale was dialed to much warmer (also varying temps. higher on the lower end of the scale. particularly idle, and off idle speeds) temps since the average ambient temperature around here is pretty high compared to where you're at, I'm assuming. I was seeing about a 6% average difference in fuel trims in CL between DI and PI. Of course the difference was not linear, though predictable.
Edit: after changing the Port injector flow scaler to -6% from stock fuel trims have gone too far in the negative above 2.0v and also below 1.7v MAF. Will go back to a higher number for the port injector flow scaler. May have to look into getting something that will log the PI and DI injector quantity and adjust there as @
Kodename47 suggested to really nail this down.
This was the amount of error with -5% value from stock
This is after changing the value to -6% along with small changes to IAT compensation. (214.xx vs 216.xx)
I think I'm probably spending too much time trying to "fix" things and it's backfiring.
