Isuzu NPR Diesel engine continues to run with key in off postion

I have a 1986 Diesel NPR truck that runs great, but a mouse got in and chewed up the vacuum lines. I replaced them, but now when I start the truck, it will not shut off unless I pop the cab and manually pull the fuel kill lever. It also will not shift into overdrive any more. And it stays in fast idle, unless I turn the key to "off." When I do that, it continues to run, but with no fast idle. Before the mouse got in, the truck ran beautifully with no problems.

Any Ideas what is wrong?

There is a solenoid attached

There is a solenoid attached to a cable that connects to that fuel cut-off. I had the same problem. Check the fuses to see if thre are any blown. There is a fuse specifically for this solenoid.
If that is not the problem, try supplying power directly to the solenoid and seeing if it works. If it does, trace the wiring to see if there is any disconnection. If it comes to that, it will be fun since the wiring runs back, over the transmission and up the other side where it runs into a wiring harness with a ton of other wires. If you can trace it to the plug under the cab, try supplying power to that. If that works, the problem is in the cab. If it doesn't the problem is in the chassis wiring.
I hope this helps.
jonathan_roux@hotmail.com

I HAVE THE SAME PROBLEM WITH

I HAVE THE SAME PROBLEM WITH MY 97 W-4....I FOUND THE CABLE FROM THE ELECTRONIC FUEL SHUT OFF CONTROL FRAYED & BROKE....QUICK FIX....I NSTALLED AN OLD FASHONED CHOKE CONTROL LEVER FROM PEP BOYS TO TURN FUEL SHUT OFF LEVER ON OR OFF....WORKS WELL....BUT WILL DO PROPER REPAIR SOON

WOODY

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