weird issue

[Street Legal]

Hello

am having a trouble with 99 yukon the car missfires, am getting P0339 code checked for poor connection at the crankshaft sensor and the PCM found no problems,i also checked the crankshaft signal with a scope and could not find anything the line is smooth, the problem happens after 10 to 20 mins from starting the car.scanned the car with HPtuners and you can see when the problem happens the RPM hits 7K from idle without touching the gas pedal.

here is a log

[Street Legal]

any ideas ?

[mcfarlnd]

is the sensor still good? is there a spec on the sensor itself to check or read out?

[vette_doc]

crank sensor wiring is short to ground (near headers )

[Street Legal]

the car is bone stock the waveform of the crank sensor signal is smooth and steady , it happens when the car reaches 80*C