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lll2for3lll 08-20-2011 03:13 PM

Question About the PCM....
Does the PCM automatically adjust spark when you use higher octane gas?

lll2for3lll 08-20-2011 03:24 PM

Re: Question About the PCM....
Just answered the question myself with a quick phone call. I guess this thread can be deleted.

06RC22 08-20-2011 03:30 PM

Re: Question About the PCM....
you could post the answer you found for others to learn from.... just sayin

lll2for3lll 08-20-2011 04:00 PM

Re: Question About the PCM....
I didn't get a straight forward answer but yes it does.

But you would have to buy and aftermarket tuner to adjust the timing and so on.

The PCM only adjust so that it would burn it properly.

Sorry. I'm still a little confuse with it all.

soontobesrt 08-20-2011 05:46 PM

Re: Question About the PCM....
TMK: The PCM will adjust the timing if the knock sensor detect pinging in the engine but this is all within certain parameters. If you run a higher octane the engine has no way of knowing this and will not increase timing, it has to be done manually w/ tuner. Only auto adjustment come from 02/knock sensors and using higher octane will not trigger those.

Only when you run lean/rich or timing is off (potential damage creating situations) does pcm compensate, not a performance type thing sadly :/ Hope that helps

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