Hi there, this is my first port, but I'm a long time lurker/researcher. I'm trying to dial in my VE table on my '99 C5 6-speed. The only mods are CAI and Long Tubed catted headers.
This is my first time tuning, and so far it's going well and I've learned a lot. I'm not trying to reinvent the wheel here with my VE table, this is more of a learning tune as it's still a stock motor and stock VE table. I followed all the steps to set myself up for a Open loop VE tune, targeting a 1.0 Eq.
My question is this - I hooked up my WB and went out logging one day recently it was chilly out about 50 degrees. Got a ton of nice date, and the fuel map was rich, between -12% and -4% all throughout. Great easy peasy.
I did not make any changes to the VE table, and went out logging the very next day to get some more data, now it was sunny and much warmer, almost 70 degrees. But I notice my IAT was much warmer 85+. Now the same VE Err table is showing 2-10% lean in all areas (my WB maxes at 1.09 EQ, so maybe leaner in some spots).
Now the only variable that changed was temperature.
Is this normal? How do you tune a moving target? I notice that stoplight to stop light, as my underhood temps creep at extended red lights, my EQ leans out, the richens back up after driving a bit.
Do I just set my IAT tables to read one temp (90?) while tuning VE? I haven't come across this type of situation in my study material.
I understand a load bearing dyno with underhood temps being steady is the ideal way to tune, but a street tune is what I'm after at my novice level.
I plan on tuning the MAF next, and when done going back to letting the PCM blend the two together.
Thanks for reading