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Car won't shut off

977 views 9 replies 7 participants last post by  chatas1 
#1 ·
So the car didn't use to do this but after I hooked up the factory tach (it wasn't hooked up from the previous owner) this problem started. Coincidence? It's a 67 cougar gt390. Any ideas? Thanks
 
#3 ·
I know that the black wire on the tach connects to the pink resistance wire. Wouldn't that preclude the full 12 volts back feeding? The car is an automatic so the tach isn't original to the car. Pretty sure the dash wiring isn't set up for it either.
 
#5 ·
Does it keep idling smooth like it was running and never turned the key off or sound like it's missing and eventually spits and runs backwards? No possible way hooking a tach into an ignition feed key controlled would cause that. A high/lean idle would. Dieseling? Or, the lead you thought was ignition/tach, is a full time hot like courtesy lights?
 
#9 ·
Turn off the ignition using the key. If it keeps running, pop the hood and pull the brown "I" wire from the starter solenoid. If it quits replace your solenoid. If not, pull the plug on the voltage regulator. If it quits, replace the regulator.
 
#10 ·
The plot thickens.... I did the pull the wire and disconnect the regulator trick and it didn't stop running.. NOW, the coil is getting super hot... I bought this car with the dash "dangling" and some wires disconnected. I disconnected the tach and like I thought, the car would fire and then stop because of breaking the circuit. The other thing I noticed... There are two ignition switches in a box in the trunk.. Sees to have been an issue before.. Ideas?

Thanks
 
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