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Old 12-28-2018, 03:17 PM   #17 (permalink)
stefanv
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Location: Ontario, Canada
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2001 Saturn - '01 Saturn SL1
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Quote:
Originally Posted by Piotrsko View Post
thought about this for a while: I think the problem is that the CPU is looking for a tach signal which it won't get with the engine dead and not spinning. Obviously, empty cylinders/ engine compression during coast will act as a coast retard. So: your kill relay will need to add some sort of PWM signal to the ECU tach input that looks like the engine is running at some RPM at or above idle.
I guess what I really need is something whose speed is triggered by the fuel injector pulses as soon as I turn off the power to the fuel injectors. Something that pretends to be an engine based on the fuel the computer thinks it's feeding the engine. I'll need to do some diagnostics to determine the relative timing between the FI pulses and the tach signal, and then whip something up to fake this out.
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Stefan Vorkoetter: Programmer, hobbyist, amateur watchmaker, pilot, and collector of fountain pens, slide rules, calculators, and watches.

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