2003 Chevrolet Impala Engine Cranking With Key Removed

Ignition switch causing car to not start or electricla problems.

Hey just wondering if you would know what would cause a 2003 Chevy Impala to turn over without the key in it

Mechanic JK:
Was there any work done to it recently? Does it just crank and crank till you disconnect battery or something?

New transmission but it did it before that and yes on crank till you pull the starter relay or disconnect the battery or turn the key to run
HMM. Try swapping the relay with another one. The only other thing i can think of would be a bad ignition switch. Any aftermarket alarm / remote start ?

Tried the relay and no alarm.

OK. The only way to get power to trigger the relay would be a bad ignition switch or shorted wire. Switches are very common. While it is cranking, try tapping on the key cylinder withe small hammer.

Ok and the pcm got wet would that cause it

How did it get wet? Flood car? Let me look at something, be back in a few minutes….

Not sure but when i pulled it out of the air box it was wet

Sounds like it went through water and engine sucked it up. OK, PCM grounds relay after seeing signal voltage from ignition switch. So you would have to get a schematic and test for either a signal from ignition switch telling PCM to crank is shorted to voltage, or the PCM is grounding relay when not suppose to.

Ignition switch causing car to not start or electricla problems.

GM theft system ignition cylinder.

Ok thank you I’ll try the switch first.