Is it normal for my A/F to change between seasons?
Long story short. I run a Dynojet wideband commander and have been forced not to dip into boost lately. My car has been in hibernation for most of the winter but I recently have taken it out and I have to immediately lift because the A/F goes 13.1 and higher at WOT. It was tuned perfectly at the end of the summer with 514RWHP and 11.8 A/F accrossed the board? Is it the cold air or is there something else going on. FP is normal, should i just increase m PE tables and have a separate winter/summer tune?
FWIW my current PE tune:
Code:
1.129 1.129 1.129 1.129 1.129 1.126 1.126 1.15 1.155 1.226 1.286 1.295 1.295 1.339 1.406 1.434 1.458 1.575 1.575
Re: Is it normal for my A/F to change between seas
Nobody huh? Everyone must live in warm climates i guess :huh2:
Re: Is it normal for my A/F to change between seas
If you are running a SD tune then its likely to run like that. MAFs are more consistent over varying environmental conditions. Another thing is to look at your LTFTs at WOT. If they are non-zero you could be getting fuel anomalies carried over from poor closed loop fuelling.
Re: Is it normal for my A/F to change between seas
what is your "commanded" afr ratio?
with that PE table, it appears to be commanding a 9:0 or so ratio.
Ryan
Re: Is it normal for my A/F to change between seas
Some areas have "winter gas" and "summer gas" formulations.
Whether this pertains to you I have no idea.
You will see a verying spark advance and enrichment based
on IAT. The latter would not affect closed loop though. If you
have a car where the fan temps are set high (like stock) the
engine coolant temp will be very different in winter where you
have great cooling air than in summer; more adder / multiplier
stuff going on that tracks ECT.
That PE table is crazy high at the upper RPM. It looks as though
it's trying to make up for a really bad fuel fade problem, but is
there really one?
