[165th]

Hi, my parents '66 Grand Prix is having starter switch issues.

It began with the starter switch cranking the engine intermittently in accessory position and in ignition position before start position.

So, after installation of a new starter, new ignition switch and even trying a new key assembly, the following occurs:

Accessory and ignition positions give proper power to radio guages etc. when the key is turned to start, nothing happens. No bump, or any response.

The starter has been tested by jumping the S pole to the 12V power pole and the solenoid kicks and starter turns.

Voltmeter shows 12 Volts at the power pole and the S pole of the solenoid when the key is off.

One question is: What is the method for automatic transmission lock out from starting? It's acting like the gear selector is sitting in Drive trying to start, and I couldn't find how the gear selector lock out shunts/unshunts the starter when in Drive/park. We tried running the center console gear selector from park to drive and back but that didn't help.

Any suggestions or help is appreciated.

[stevep]

When you turn the key to the start position, 12 volts goes to the S terminal via the purple wire and fires the starter. The purple wire runs through the neutral safety switch, which is located in the console.
How is the plug on the back of the ignition switch? They are famous for melting.

[165th]

Thanks for the reply. I'll have dad chase the purple wire through the console to make sure it is sound through the console neutral switch.

The wire harness is in good shape, and the plastic housing that receives the blades from the switch is not melted.

[165th]

It turns out the replacement starter was defective. Sometimes the least expected places to look can cause headache's. The good news is they are on the road today heading for Louisville KY for the POCI.