Yes, that was the part that I did not include in my description. New lock cylinder and key was the first part replaced, then I replaced the actual ignition switch located a little further under the steering column, then I replaced the starter solenoid.
Let me know!
Now lets check for spark. I want to find out the very second you stop cranking, if there is any spark. You might need somebody to help you out and crank it over for you.
This is really important!
Excellent! We are getting somewhere!
Now, we have to figure out if we are loosing power to the coil when this happens, or a ground signal to the coil when this happens. We should be able to test this just with the key in the on position.
So... turn the key on and check the wires going into the coil. We should have power to at least one of them.
The test light goes out when the key is released. Further playing around with it it still runs great if I disconnect the lead to the solenoid after it starts. When I ground out the lead it shuts off, and when I plug the lead back on to the solenoid it shuts off.
What we are going to do next, is check for power with the key on on this same wire but down further in the circuit. I want you to go to splice 112 and check this same wire for power.
Splice S112: Engine Harness, Near Take Out To EGR Vacuum Regulator
Or, you could go to splice 105.
Splice S105: Dash Panel To Engine Harness, Near Take Out To Ignition Coil
Either way, its the same. You should have power on this wire with the key on.
Here is the wiring diagram.