Hello all, To start I would like to say that I searched this with no luck.
When my 88 Trooper 2.6 is in the auxilary key setting to listen to tunes the I can here the fuel pump buzzing away. This is not right and I don't know where to start, fuel pump wiring or relay? Any ideas.
TIA, Grant.

No, that ain't right...

Sounds to me like a previous owner has butchered something.

I'd start by carefully looking around and trying to identify any obvious butcher jobs on the wiring, then go from there.

The fuel pump should definitely NOT run without the engine running. It shouldn't even run if you turn the key to the RUN position (without the engine running).

Yes, the previous owner has made a mess of some wiring. Where would I find the relay? I don't really want to pull the tank to see how he may have screwed that up. Any hint will help. Thanks.

The fuel pump relay and fuses are in the fuse box on the driver side inner fender... if the cover for the box is still there, you should be able to tell which is which.

Pull the fuel pump relay and see if the pump still runs in ACC position. That might tell you that at least everything is "normal" from the relay on back to the tank.

The way the pump is spoza work is pretty screwy louie... when you hit the starter, the pump runs, when the engine starts, the main relay pulls in which in turn pulls in the fuel pump relay, and it stays on until the engine stops.

Anyone else experience this? Any other hints or tips are appreciated.

Unless someone else's truck was butchered the same way yours obviously was(by the same person?) I doubt anyone else would have the same problem.

If you wanna fix it, you need to get a schematic, understand how it works, find what's wrong, and fix it...

Did you look for/find the fuel pump relay ?
Did you pull it and see what happens ?

Yes, found the relays and pulled it while the pump was running in ACC. The pump shut off when the relay was pulled.

Just a quick update. I pulled the fuse box and below was a mess of re-routed wires and what appears to be the previous owners attempt at bypassing the factory relay set up. The thing is he took power for the fuel pump from an accesory source. With a friends help we instead took power from the #6 fuse, which only supply's power to the pump in start and run. So, problem solved. Thanks again.

Great!

Keep in mind though that the way it was originally wired was a "safety feature": When the engine stops, so does the fuel pump. That way if there's a crash or something, then the pump shuts off if the engine stops instead of spewing gasoline all over the place... so ya might wanna look into trying to get it back the way it oughta be.

I'm willin' to bet that the guy that did the re-wiring had actually experienced a defective alternator...