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LS6 injectors wont fire

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I am new and tried to use the search feature on this but got nothing. This is my first post, and im really excited to start using everything this package has to offer. Before I dive off into the issue at hand, heres a little about the situation.

This is for a customer car, so time is a little important. I currently have a Factory Five GTM that someone built in the years past, using an 01 Corvette donor. The wiring appears to be factory Chevrolet (not a swap harness) and imho is atrocious. However, there hasnt been an issue until recently. I currently have access to VCM editor/scanner.

The issue: Car was parked in the garage some time ago, and now has no injector pulse. What I have checked: switched 12V at all injectors, spark is present, fuel pressure present, have pulled injectors and manually provided power and ground (while still in a pressurized fuel rail) to verify they are not stopped up, they sprayed, I have an RPM signal, verified that VATS is disabled in the computer, No DTCs currently present.

What else could I monitor using VCM that may help point me in the right direction of the culprit? Is it the PCM Itself?

Add these to the list of things to check when you run out of other things - fuel pump is actually still working, electrics and fuses for fuel related stuff, fuel filters, actual in-the-rail fuel pressure, map/rpm/airtemp/tps/etc signals all working correctly in the logging/monitor software, re-flow the injectors if you really run out of options if it ran ethanol based fuel and left some in the tank and lines etc at all.

Good luck - let us know what you find - hopefully its all nice and easy for you and you find your answers pretty quickly :)

Did a log through VCM scanner, it registers a value for every sensor while on and while cranking. It does not, however, register any duty cycle or on time values for the injectors. Could the injector driver in the PCM be shot? I attached the log I took. This is my first time using any of this.

Attached Files

I don't have hp tuners to view the log sorry :\

In theory - the ecu would show injector output in the logs even if the driver was blown - the code is still telling the injector to fire and thats what is generating the logs.

Is there an immobilizer in the factory ecu that's sprung into life and is preventing fueling maybe? A tickbox for disable injectors? Something like flood clear mode?

Wish I could give you better ideas sorry :\

No problem, I have checked and made sure that VATS is disabled, but outside of that I havent found anything that would cause a problem with the injectors firing. I am tempted to just buy another PCM, flash it with the tune thats on this one, and see if it works. I dont really know what else to do, and I hate guessing on things.

The issue you describe would indicate that the injector drivers are not functioning. Check whether the injectors are ground side switched or power side switched. The ECU will have either an NPN or PNP transistor to control the injectors. If they are power switched, check the shared ground. If they are ground switched, it would most likely be an issue with programming. Drivers almost never fail unless a high impedance system is matched with low impedance injectors.

In my opinion, there's probably an issue with either the plug itself (corrosion on pins) or the programming is in some way corrupted and is not commanding the drivers to open the injectors.

Finally, check whether or not your system actually pulses injectors during cranking. I've seen systems where there is just a quick burst at the beginning of cranking and once there is a run-up signal from the crank position sensor, it'll start pulsing. Check CKP input with a scope as well to confirm that the ECU is receiving an engine speed signal.

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