[PontiacsForever]

I have a 1969 GTO. I can start the car fine, but when I try to shut it off it continues to run. I can even take the key out of the ignition cylinder. I stop the engine By starving the car of air by covering the carburetor. Once the engine stops, the Oil and Gen lights come on in the dash. I have to disconnect the battery otherwise the battery will drain. When I reconnect the battery, Oil and Gen lights come on again, but the car starts fine and the process repeats itself.

I have read about alternator feedback. Any idea on how to test the alternator to see if that is the problem. Also, is there a way to test the ignition system or ignition switch to see if that’s the problem.

Thank you for all your help.

[Scott Thelander]

Welcome

did you just tinker or repair or replace any items

or

did it just all of a sudden happen ,,,, ?

Scott

[Kenth]

I would take a close look at the rod between key tumbler and the ignition switch down on the steering column for proper action.

[Tarl]

I have had carbon buildup on the ignition switch down on the column that has caused this, kept wires connected.

[PontiacsForever]

Scott. No repair or tinkering.

Kenth, I checked the rod without dropping the column and it is moving back and forth, but I do need to make sure it is still connected

Tari, I will clean and maybe replace the ignition switch once I drop the column.

Any other ideas. Out there?

Thanks

[Joe's Garage]

Or it could have come out-of-adjustment just enough to cause this.

Some aftermarket ignitions (like MSD) will keep the car running due to the voltage feedback thru the GEN lamp in the dash. They sell a diode to put into the GEN power wire to stop this.

Try starting the car with the hood up. Turn the key off. From your description, it sounds like it will keep running.

Unplug the two-wire plug from the alternator. Did it stop, or is it still running?

If it died, it's feedback from the GEN light bulb. If it kept running, I'd take a hard look at the ignition switch and wiring.

Good luck!

["QUICK-SILVER"]

If it's got an external voltage regulator un-plug it before you hook the battery back up. If that stops dash lights from coming on you've found where power is getting to ignition.

Clay

[lfdsteve]

I had that problem w mine. Turned out to be a overheated, melted wire right where it comes out of the fuse box connector under the hood. Took a thermal camera to find. Drove me nuts for weeks!!!

[PontiacsForever]

Joe and Quicksilver. No aftermarket ignition. Tried disconnecting the Alt. Still kept running

Ifdsteve, I will give a hard look at burnt wires.

Also, I still need to get at the ignition switch on the column. I really hope to find the problem there.

[PontiacsForever]

Guys, so I disconnected the alternator, pulled out the ignition switch after dropping the steering column and then reconnected the battery. The Gen and Oil lights still come on, which to me, means the car is still in the “run” position for the ignition cylinder.

To me, this seems odd since everything is disconnected. Does the car somehow retain the last position of the ignition cylinder?

Thanks for your help.

[gto4evr]

"pulled out the ignition switch"

as in you took the switch off the column and left the harness connected?

or disconnected the harness from the switch?

the switch will stay in whatever position the rod had it in so if it's still connected to your harness, it'll do whatever it was doing before you removed it. the rod pushes the slider assembly to different positions on the switch, the only one it wouldn't stay in would be start since that's spring loaded and would push it back to run once the key is released (and if the switch was off the column rod, it would just push itself back to run.

if you have the harness disconnected from the switch and it's still doing that, then you've isolated the issue to the wiring as others have said, sounds like a short between the always hot and the ignition circuit.

if the problem goes away once you unplug the harness from the switch, then it sounds like the switch contacts are shorted so they're still making "run" contact in the off position. (as long as the switch was already in the off position and you didn't leave it in run)

[PontiacsForever]

GTOforever. Thanks. The switch is disconnected from the harness.

Sounds like it may be the wiring. I’ll also try Quicksilvers idea of disconnecting the stock external voltage regulator.

Everyone, any other ideas are always appreciated. Thanks

[Half-Inch Stud]

Try borrowing a differnet IGN switch.

Also the Starter Solenoid ought only have 1 thin wire (S or R, i forget which) not two thin wires. If there is two thin wires then disconnect the white wire.