Oh now I'm mad. Yesterday I went to move my Camaro to trim some bushes near it, and it wouldn't start. Cranked and cranked, no fire.

Hooked up my AutoXray and it showed no codes. Watching live data injector pulse stayed at 0.0ms while cranking, and RPM remained at the 0-50 it shows when it's not even being cranked. Popped off the coil wire, no spark. Quickie checks showed power to the Opti and the ICM. Just to try, I connected a known good ICM, no change.

Later, after I charged the battery back up after being drained from all the cranking, I hooked up my laptop with Datamaster logging. It too logged no RPM cranking, 0 injector pulse, BUT it highlighted DTC-16.

I only have access to the AutoXray and the laptop and a test light at the moment, can anyone think of anything I should look into while I wait to borrow something expensive to graph out the high/low res signal lines?

 

DTC 16 is loss of low resolution pulse. That shuts down the fuel system = no start. IF there's no low res pulse, the PCM can't determine the RPM. Many Datamaster scans show "50" RPM when the engine isn't running.

 

Thanks Fred, thats what I was afraid of.

Bleeping non-vented opti. It's maybe 2 years old, roughly 10,000 miles on it. And yes, it was a new GM part. I guess MSD this time...at least it's vented.