Bink

What is the "Dynamic Air" PID ??
Below 60*C it seems to nearly equal MAF gms/Sec.
At and above 80*C it's greater than the MAF reading. What is it measuring in Grams per second?????TIA
joel

ChrisB

Off the top of my head isn't the "calculated" g/sec value based on SD calculations?

Bink

Thanks Chris. So, I guess it's using RPM, MAP and IAT. Is it also using TPS to correlate MAP/Load??
Tonite I was playing with IAC and Running Airflow (Idle Air in Gear) values in my Vette. It's setup for Open Loop.
Anyway, it was surging and initial event seemed to be an increase in TPS,from ~7% -> ~11%, along with an increase in Dynamic Air to 25 from 9 (This is at idle- I haven't touched the pedal). Then Timing would jump to 30* and Pulsewidth widens to 5.8 - 6.0. RPM drops from 1200s to 800s and AFR goes to 10.
Then the reverse, of course.... back up to 1200s RPM.


Where the hell did that come from...30* of Timing....shouldn't be more than 26*- even if we convert Dynamic Airflow to gm/cyl and use Hi Octane as the Look Up!!!???????????
I'm just trying to understand what was happening????


I went back to previous IAC and RAF values and it idles fine now. Thanks again for the Input.
joel


O.K. I found it......, maybe ..... - Maximum Brake Torque Table- If PCM is using this table then we could have 30* Timing at .3 gm/cyl. When does the PCM attempt to achieve Max Torque i.e. use the Brake Torque Table???? At Times of constant RPM/TPS????...i.e. non-acceleration?