Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
Hello, my name is***** battery is disconnected with vehicle running it causes charging system to go full blast which can damage electrical components. Considering there was no problem before it sounds like your PCM may have been damaged. I'd monitor injector pulse on cylinders 2 and 8, if pulse drops when vehicle warms up then replace the PCM. Here is a wiring diagram to help with testing, let me know if you have more questions. Thanks.
The output would be related to injector circuits so that would be place to start. Let me know how it goes, thanks.