Question Time

[IJ.]

I'm going to cross post this on the FB Group as well,

1) Having trouble with PE, I'm trying to sort my VVE Table but have noticed it doesn't ever seem to go into PE mode going by the V2 and logs.

2) It's more than likely something stupid I've done in my tune so please be gentle if you find something.

3) I'm logging AFRATIO_M in BBL I'm assuming this is what will tell me the commanded AFR?

Thanks in Advance guys!

Ian J

15682
15683

[swingtan]

AFRATIO_M is correct.


PE enablers are set to...


MAP: 15kPA (very low)
ETC-TP: 12 to 19 (very, very high)


The trick here is that the PE TP% table has a non-linear relationship to the measured ETC-TP %.

See here..... http://forum.efilive.com/showthread.php?6461-Best-activation-of-PE-mode

From your tune, you will need to reach a measured 40% to 50% TPS before PE will activate.

Personally I hate the way GM does PE. I go back to the old power bypass valve method and set set MAP to be high (70kPA to 80kpa) and set TPS% to be very low (5% at low rpm and 1% at high RPM). The MAP will always head towards barometric pressure when the engine is under load, no matter how much throttle is used.

Simon.

[IJ.]

Thanks Simon, still wrapping my head around this, so I'm adjusting B0157 to 80ish and B0156 to 5 at low rpm and 1 at high rpm?

[swingtan]

For dialing the VVE, I'd go..

{B0157} - 70
{B0156} - all 3%

Then when setting back for normal driving, look at hoe the car runs, where the MAP normally sits and average TPS in the logs. Adjust the PE enablers to suit the driving style and what feels best. Bigger cams will want a higher MAP setting as they may be close on 70kPA at idle.

[IJ.]

Thanks again, all done will go try it now :)

[IJ.]

Much better thanks Simon!