I have a 2001 Chevy blazer, and when I put the key into "run" to turn the radio and lights on, the engine will start up and continue to try to start it self. The start well not disengaged, so I replaced the starter relay in the fuse box. Still happens, so I replaced the starter with a brand new one, still was happening. So I bought a new tumbler because the key turned alittle sloppy and also replaced the wires coming out of the tumbler and it STILL is happening. I've replace everything the could go wrong and the truck it still firing up in the on position and does not stop.

 

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