[c4c5specialist]

Hi there,
Well, there are alot of different ways that the computer compensates.
Also, if your battery is disconnected, you need to perform an idle relearn, otherwise, it may take a while for the PCM to correctly learn its idle setting. Also, you may have had a gas situation, and the knock sensors work, and retard the timing.
All of these should be taken into consideration.
Best to you, c4c5

 

[Bob57]

C4C5
Thanks! Does that mean that the rumors of the computer learning according to the driving habits is just rumors?
Speaking of gas, we now here in CA are going to have 91 octane instead of 92 since they're phasing out MTBE. Does anyone have an opinion on using octane boost of some kind? As far as I know the "104 octane boost" does not have alcohol. I'm thinking that if the octane is higher, than the computer will allow more advance. Any opinions?
Thanks, Bob

 

[SteveYelloZ06]

I have an opinion on octane boost. I feel it is oly neccesary if your car runs poorly on low octane fuel. If your car runs fine on 89 octane, then I don't believe that adding 93 octane does you any good. I have been wrong before though.

 

[Bob57]

Steve,
Yes the car runs fine, but does it make sense to you that on lower octane fuel the computer will not allow as much advance due to a knock senser? If that's the case, maybe higher octane will cause the computer to allow more advance which could possibly mean more power even though it runs fine right now. What do you think?

 

[c4c5specialist]

GM says that 91 or better is fine, and you will be fine with no loss in performance.
Best to you, and you dont need octane boost, c4c5