No RPM's Randomly

[storx]

2010 Cobalt 2.2L Auto
My parents car is having issues again, about 6 months ago it threw codes for crank position sensor after stalling at a red light randomly, so i replaced it and the car has been fine... today the car starts stumble out of the blue and i thought it died because the rpms were showing 0rpms, but when i went to turn it off and back on to start it i heard the engine shut off and turn back on.. confused me... Took it to have codes read and NOTHING.. car sits while we eat lunch and the rpm gauge is back to working fine and its driving and shifting like normal.. get 3 stops down the road and it does the same thing, the rpm gauge goes to 0, the car seems low on power and shifts like its confused...

Ive done googling, but i dont really see anyone having a no RPM condition like this, i just see erratic RPMS issues all pointing to crank position sensor...

 

[roosterk0031]

2010 Impala, gauges would shut off while I was driving and occasional non-crank when startup, again only when I was driving. Well I almost never drive it unless wife is in passenger seat. It had some chaffed wires that would ground out only if someone was sitting in the passenger seat. Never happened to her driving cause most of the time she's driving it alone. If it wouldn't crank just had to have passenger take some weight of the seat. It always ran fine though. I don't think it ever threw a CEL.

Was anybody in the passenger seat?

 

[YelloEye]

Is it just the RPM gauge that drops? everything else in the DIC working? Sounds like a loose wire or bad cluster.

 

[storx]

Is it just the RPM gauge that drops? everything else in the DIC working? Sounds like a loose wire or bad cluster.

yes it was only the rpm gauge, but if you turn the car off when it does it and restart it the problem goes away and the car gains all of its power back and no longer shifts weird

 

[YelloEye]

Sounds like a wiring issue.