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C6z electrical gremlin help!

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Old Mar 15, 2019 | 03:21 AM
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Default C6z electrical gremlin help!

Need help bad, my C6Z is going crazy with issues. Now on battery three, Two Duralst and now shelled out for an Optima blue top. Been fighting No key fob detected, no starting (but it cranks), very weak start, noisy knock sensors according to the pcm. Now I'm having a hanging/rising idle and the car just shuts off if the tires spin even with traction control off. All grounds checked and they're good. No blown fuses either. Could this be a problem with the PCM itself? Anyway to check ? I'm all ears because I'm pulling my hair out at this point!
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Old Mar 15, 2019 | 09:14 AM
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sure sounds like a connection problem, did you clean your battery terminals and inside the leads that connect to battery? i know you said you checked grounds, well check them again, unbolt them from frame, brush off the oxidation till they're shiny, bolt them back on. check wiring to ECM, look for shorts, etc. Is your alternator working right? why did you change 3 batteries, do they keep dying? check (and recheck) wiring on engine, like coil driver grounds, etc.

What you're describing, things like weak start, sure sounds like you have a higher resistance somewhere in the wiring harness than you should. or your charging system is flaking out and killing your battery.

and probably more importantly, post a list of all diagnostic codes.

Disclaimer: I have never experienced electrical gremlin's with my vette, i don't have any corvette specific insight, but if it were my car, that's where i'd start.

Last edited by luka2sb; Mar 15, 2019 at 09:16 AM.
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Old Mar 17, 2019 | 02:20 AM
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Check your spark plug wires? check your connection at the starter solenoid? IT comes loose and or breaks.

Get a voltmeter and do the diagnostic checks from the alternator to battery, parasitic amp draw tests, ground tests etc

It could be the ecm. When mine went out the car would die and tell me service charging system, traction control etc etc, no key fob detected. It may just need to be re flashed or replaced.

search all electric troubleshooting posts by Dano523 https://www.corvetteforum.com/forums...duser&u=465024

Last edited by Got uid0; Mar 17, 2019 at 02:22 AM.
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Old Mar 17, 2019 | 10:15 AM
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^sounds like you had a similar issue, did the new ECU solve all those issues ?

So I checked grounds again everything is fine, I'll try to do a parasitic draw test soon just going to wait for extra long leads. Does anyone know if I can do this with the door open if I let it sit for a while?

I recently removed the engine and wiring harness building the motor (was having issues prior to removal). Checked the clips during that time and only one that was bad was the 02 sensor clip melted so I replaced it.
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Old Mar 18, 2019 | 12:45 AM
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you dont need long leads to do a parasitic amp draw test. youtube search it

yes replacing the ecm fixed my problem. I had a tune on my car and chuck cow sent me a loaner autocal to copy off the tune. he sent a replacement ECM and married it to my vin.

If you do not have a tune the hardest part was removing the ecm.
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Old Mar 23, 2019 | 01:59 AM
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Default Thank you! Glad it worked for you!

Originally Posted by Got uid0
you dont need long leads to do a parasitic amp draw test. youtube search it

yes replacing the ecm fixed my problem. I had a tune on my car and chuck cow sent me a loaner autocal to copy off the tune. he sent a replacement ECM and married it to my vin.

If you do not have a tune the hardest part was removing the ecm.

Thank you! Glad it worked for you! How do you like the CoW BOOSTER! we did for you?

Chuck CoW
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