Displacement on Demand/AFM question

[jcmartel75]

Can DoD/AFM still be active even though it's been changed to Disable via hptuner?

I've disabled it in my tune. If I hit a cruising speed I'll get as much as 6* of KR. There's no boost in my MAF and I've read that DoD switching on can cause some KR. If it's still coming on even though it's set to Disabled, can somebody explain to me why?

I think I'll switch Min VSS to 100 and Disable RPM to 100. Perhaps that will ensure that it won't come on at all.

[Nick 2K2 SS]

Use your status bit table in the scanner to log the "DOD Requested" status bit. Then you'll know for sure if the ECM is asking for DOD. I can tell you that even in 8 cylinder mode on my Grand Prix GXP there is still quite a bit of knock retard at medium to high loads while at cruising RPM's (1200-2000). So it's not unusual to see knock retard even from the factory calibration.

[jcmartel75]

oh ok... thanks Nick. I've never even opened the status bit table. I'm still learning obviously.

I didn't log a scan under stock conditions so, I'm not sure if there was any KR as high as 6* before. I just noticed a huge jump at certain times and was wondering why that was. Normally, there's just a little, 1 or 2* but, a jump to 6* got me curious as to why. In my reading, I found that tidbit about DoD causing some so, figured I'd investigate that.

[jcmartel75]

Thanks for the info Nick. The status bit stayed at NO so, any KR I get is unrelated to the DoD/AFM. I, at least, figured out that disabling the DoD does keep it off.