Early GM obd2 question.

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crazyman
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Early GM obd2 question.

Post by crazyman »

The spark retard from the knock sensor. Does it pull it all at once, or is it variable retard based on voltage output?

Thanks.
In-Tech
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Re: Early GM obd2 question.

Post by In-Tech »

crazyman wrote:The spark retard from the knock sensor. Does it pull it all at once, or is it variable retard based on voltage output?

Thanks.
What year/engine? I'll look up the code when you provide the info.
Heat is energy, energy is horsepower...but you gotta control the heat.
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Re: Early GM obd2 question.

Post by In-Tech »

Here's a screen shot of a '96 Chevy PU Vortech 350 knock attack table. As far as I know, all GM ecm/pcm's have an attack and decay rate. So, to briefly answer your question, it ramps up to gain control and then continually tries to decay it out as long as there is no knock. Hope this helps.
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Heat is energy, energy is horsepower...but you gotta control the heat.
-Carl
crazyman
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Re: Early GM obd2 question.

Post by crazyman »

Thanks In-Tech!
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