Hey guys -

This is my first time to post a message so I'm really hoping you guys can lead me in the right direction!

I have a 1990 Range Rover Classic that has absolutely stumped me and several others as well. I thought I would come to the pros to get it done once and for all. I apologize in advance for the length of the message but I wanted to make sure you had all the details as to what's going on. So here goes...

The problem I'm having is with the fuel pump wiring (as best I can tell). I can get the pump to fire up and the car starts with no problems. I can only get this to happen when I hard wiring the fuel pump to a car battery (not installed in the car). I am using the wiring harness (female side connector) that comes right from the top of the fuel pump itself. There is a brown (negative) and a blue with white stripe (positive). I run a wire from positive fuel pump wire to positive battery terminal and a wire from negative fuel pump wire to negative battery terminal. This works with the fuel pump and tank installed in the car or if I have dropped the tank (had to use some extra fuel line to connect lines)

This is what makes me think that there is some type of shorted or bad wire. When the tank has been dropped from the car I can hook up the fuel pump (still installed in the tank itself) using the normal wiring harness (not hard wired to a battery) and it started every time. Once I put the tank back in and tried to start it (holding my breath and crossing my fingers) all hell broke loose! I was right back where I started - As soon as I turn the key to the 'accessory' position - POP goes the weasel - the fuse blows.

An additional note: After I kept popping fuses, I wanted to make sure that the pump still functioned and would start the car. So I hooked the fuel pump up to a battery again (still not installed in the car) and sure enough the fuel pump kicked on and the car started. I wanted to test a short cut - sorry to say but I was getting desperate to have the car start so I was thinking about installing a switch inside the car and hard wiring the fuel pump to the battery. Before I did any more wiring work, I decided to test my idea and run some wiring directly to the car battery (installed in the Rover) from the fuel pump harness. I quickly tried to start the car but didn't wasn't getting the fuel pump to kick on nor start. That caused the wiring to get super hot, super quick so I yanked off the connections fast.

Does this sound like anything that anyone has encountered and has a fix for? I'm sorry this was so long but I wanted to be sure and explain everything as thoroughly as I could in order to clarify what I'm up against

I'm learning a lot by working on this but I'm still not fluent when it comes to diagnosing electric problems such as checking for continuity, resistance, and using a voltmeter in general. Even with my limited experience this sounds like something is causing way too much resistance in the fuel pump wiring.

Does this sound like anything that anyone has come up against and has a fix for? Any troubleshooting tips would be more than welcome!

Is it possible that the actual wiring coming from the top of the fuel pump is shoddy? If it was jicky wouldn't that keep it from kicking on and starting the car when its hard wired to an external battery?

 

with the pump unplugged . replace fuse. if it pops you have a bad wire some ware. then you can start tracking it.

also put a inline fuse on your positive wire that you ran directly to your batery. if the fuse pops with external wirring. then the pump it self is bad. because you have taken the trucks wire harness out of the equation

also you can by pass that wiring. buy re using the plug end from the truck harness. an running new wires to the relay its self. an putting the plugg end on your newly made two wire harness. to your pump.

let me know if this helps any . i will check again later.