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67 Cutlass Supreme Ignition Short?

07-09-2013, 05:54 PM
This started when I took my 67 Cutlass Supreme out for a short drive. When I came home and turned the old, kind of worn, key to "Off" all sorts of unexpected things happened. First, the engine (1976 455 rebuilt w/ MSD & GM HEI) kept running. As I tried to get the key to work by jiggling it a little and turning it, the starter engaged a couple of times, the engine kept running and I got a little freaked out. Finally got the engine to stop by putting it in gear (TH350) and putting my toe under the accelerator pedal.

I figured the ignition switch was shot (67 is the last year the switch was in the dash), so I replaced that. Everything went back together fine, there's no way (I don't think) I could screw that up, it plugs in to the wiring harness only one way. Started the car up fine, but it still won't turn off. It seems like there must be a short that's keeping the coil hot, but I have no idea where to even start. My friends that are familiar with older GM cars don't have much to offer either.

Does anybody have any ideas, or even a sequence to go through to eliminate the possibles, in some kind of order?


07-09-2013, 07:14 PM
Basics here, check for 12v at the coil, if so back track from there to its source, sounds like burnt or shorted harness somewhere.

02-06-2015, 12:25 AM
Replace the electrical part of the ignition switch. Turn lock to accessory position and on face of lock you will see a small hole. Insert a paper clip into this hole as you continue to turn the lock counter clockwise and the cylinder will relase and come out. Then just unscrew the retaining ring and replace the electrical part. re assembly is the reverse. (Specific for 67 with dash lock)

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