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Missing injector pulses - How to narrow down the problem? 700 1990

Hmmm. Yes. Yes, I do. And they're a lot cheaper than a used ECU.

I verified that the ECU is getting a constant 7.0-7.5V signal from the ICM. I tested the "signal generator" by probing pins 10 and 23 on the ICU. It says the resistance range should be 215-265ohms. Mine measured about 180ohms with the connector attached. That's out of spec, but I didn't see any variance in the voltage to the ECU pin 1 (measured at ECU-1) nor any dropouts - neither with the Digital nor cheapo analog meter.


So, I'll check that the ballast resistors are still getting power and the injectors are still getting power. Hmmm. So long as the injectors have power, that means the ballast resistors are working.

If the injectors have constant power and they're just not being grounded, I'm going to blame the ECU. I've never heard of another ECU failure like this though, other than seemingly random error codes.






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New Missing injector pulses - How to narrow down the problem? [700][1990]
posted by  Will740turbo subscriber  on Wed Jun 11 21:13 CST 2014 >


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