Thread: MPG
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Old 08-10-2006, 10:59 AM
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Default Re: MPG

System cannot detect for NO knock, it can only detect knock. Hard to explain this...
Let's say the base tables are set for a specific octane, as long as you use this octane and do not experience any knock, the PCM does not need to change timing. If there is knock detected, the PCM will adjust the timing curve to get rid of the knock.
Basically, the PCM does not know what fuel grade you are using, it is only interested in if it is causing knock. (It's early)
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