After reading my last post I realized that I was very vague and therefore would probably not get much response. This time I'll give more detail.
My 86 240 will not shut off using the ignition key.
I have traced it down to what I think is the fuel pump circuit and here's why I've come to that conclusion.
If I pull the spade fuse under the hood (the one that sits on the fender wall by the coil) that runs from the battery to the fuel pump relay, the car will start, run and turn off using the key without a problem. If I leave the fuse in the holder the car will not turn off using the ignition key and even if I pull a coil wire to kill the engine the fuel pump keeps running.
Now I have visually checked the fuel pump relay and it is opening and closing but it seems as if the coils are getting fed from the back side instead of through the number 30 wire (the fused wire from the battery).
Now I know that the previous owner has had a problem with this circuit in the past because there was a fuel pump relay in the glove compartment that I've tried and seems also to be good. Also, they have cut one of the wire leading out of the relay and ran it to a ground on the firewall. I can unhook this ground and can make the pump stop running by turning of the key but if I start the car with the ground unhooked the key still will not kill the engine.
Why would the car operate perfectly without the main inline fuse installed yet not work with it installed if it's not a backfeed condition through that main wire? I'm looking for anything here because I'm at a total loss.
Also, what does this fuse (the one under the hood) protect? Would I be alright in running the car without the fuse or do I take the chance of smoking my fuel system?
I'm really looking for some ideas here guys. I've seen a lot of good advice given on this forum and I'm trying to learn to do my own work. Please help if at all possible.
Thanks,
Dave

 

This problem is presenting itself as something complicated, but it has to be a simple fix. You have to start thinking about this problem sequentially. The core of your problem is that the car will not shut off when you switch the ignition off.

1. The first thing you should rule out is that the ignition switch. Be absolutely sure that this is not the cause of the problem.

2. Pulling the spade fuse that feeds the fuel pump will not kill the engine immediately, after all the fuel in the system is consumed the engine will die. If you only had the fuse out for a minute or two no change would occur. If you pull the fuse and the car is still running 10 mins later then that is a problem.

3. The fuel pump relay is also suspect. It could possibly be stuck closed. Try replacing the current relay with a new one that is known to be working.

 

89_240,
First of all, thanks for your reply.....
When I pull the spade fuse (with the ignition switch OFF) the car DOES die immediately. It seems that the reason this happens is because it then gives an open spot for the power to stop flowing through the circuit.
As for the relay, we have both tested it with a voltmeter and actually opened the relay and watched it function. Everything is working just as it should.
The only answer is that there is voltage flowing through the BACKSIDE of the relay and energizing the coils and since it is not blowing any fuses it about has to be two hot wires which have come together. I'm hoping that someone can give me advice on where to check for this wire to wire condition.
As I said before, I can pull the spade fuse and the car will start, run and shut off just as it's supposed to do. It's only when I insert the fuse in the holder that this happens. Since the relay can no be picking up it's juice from the battery (with the fuse out) then it has to be coming from another source. That source is what I need to find.
If someone can tell me where to check for this conditon on the car it would help greatly. I don't know where all of the wires run for this circuit so I'm not sure where to even look for the crossed wires.
Thanks again for answering and any ideas would greatly help. I'm pretty much lost when it comes to electrical circuits and have been relying on my brother's expertise to get this far.
Dave