I can't turn it off.

[RapidRabbit]

I took the Mustang to work this week and when I got home I turned the key off and took it out and the car kept running. WTF

I put the key back in and cycled it a couple of times and it kept running. It finally shut off when I put the key to acc.
I'm thinking my engine knows it's getting replaced and doesn't want to die. :lol

Does this mean I need a new ignition switch?

 

[gotstang]

Sounds like the switch itself (not the part you put the key in) or a stuck starter solenoid.

Being a 1970 car, you've got a long road ahead of you to replace the switch since IIRC it's the one year that's not being repop'ed and it takes some "creativity" to replace it with whatever they do make.

 

[Jonk67]

When this happened on my '67 it was the solenoid, new defect! I tried the ign. switch replacement first and it still wouldn't shut off until I pulled the batt. cable. Swapped out the solenoid for a BWD heavy duty model and all was well.
Jon

 

[David67]

It's a stuck starter solenoid. Just replace it and it will be fine.

 

[Anonymous]

I agree with David.

 

[RapidRabbit]

I will try replacing the solenoid. I have an extra one in the garage. I seem to be going through a lot of these.