So, I have a 2003 Disco HSE. I was driving and all of the sudden the engine just stopped for no particular reason. Engine temp normal, plenty of gas, etc. Then it wouldn't crank back up. Let it sit then came back and it cranked right up. Diagnosed at Euro mechanic as bad fuel pump (stalled again on way over there). Replaced Fuel pump it but it is still doing the same thing!! Now again it dies while driving after a few miles, then won't start until an hour or so later - highly annoying. Anyway, I'm thinking now after reading on here that it may be the crank sensor. here's my question-- Would a bad crank sensor cause it to die WHILE driving?? or simply keep it from starting? Please help me!!!!

p.s. They also told me it was highly unlikely to be the Relay as they rarely go bad

Stranded at Starbucks

 

Fuel pressure can be checked at the fuel rail. There is a shrader valve on there.
You will usually throw codes (cel) w/cps. Misfire. But they have a tendency to act up after warm. Some have tested by squirting cold water on it to test it cool versus hot (acting up)

 

Sounds like you replaced a fuel pump when you should have replaced a Crank Sensor.

Your mechanic should have confirmed fuel pressure or lack of fuel pressure.

Ps I have replaced a crank sensor and a fuel pump relay. Separate instances, where they both failed.

 

If you want to rule out the relay switch it with an adjacent one. The relay is located in the fuse box under the hood. Locate the relay and switch it with the one in front of it or in back of it.

And yes, if the crank position sensor fails, the engine immediately cuts out - while rolling down the road. In the early stages of failure Once it cools down it typically the engine will fire back up.

 

I think you're right about having replaced the fuel pump unnecessarily. I have a crank sensor on order from Atlantic British, so hopefully that will fix the issue. I'll also switch around the relays just in case. This is a very irritating and dangerous problem and has left me stranded several times. I'll update you on what I find out. Thanks for the support!

By the way, I'm assuming I have to remove the front drivers (American) tire in order to do this. Does this sound right?

 

tire off helps. sensor is tucked away. I got mine from above while I had heads off, so that was easy. you can get to it from below, with a little contorting. I have also seen picts of a guy cutting into the inner wheel well, to make an access.

 

I changed my CPS laying on my back in the yard. It certainly helped that I have three inches of extra lift, but accessing the plug proved very difficult; I had to work my finger tips through globs of caked-on oil (dryed up sweat from all that horsepower).

I did not remove the front drivers side tire or wheel well. Land Rover choose a small displacement motor designed to fit in a gigantic engine bay for a reason

 

Alright, the verdict is in: it was never the fuel pump to begin with (or the relay) but rather the CRANK SENSOR that was the problem. I switched it out and haven't had the problem since. Just wish I knew this before I put in a new fuel pump!! Anyone need a used one? Let me know! (Disco II -- pump w/out pressure sensor-- truck has secondary air, but I don't think this matters--WF101060)

As an installation note, I did not need to remove any tires or drop exhaust, but I did LOOSEN the exhaust so I could force it over to the side a bit - that 1/4 inch makes a huge difference in getting your arm in there. So now I'm covered in scratches and bruises, but it's nice knowing I didn't have to spend any $$$. In hindsight, I would find a 12 year old boy w/ little arms and give him $20 to reach up there and switch out the switch from the harness - takes 5 seconds if your arms are tiny enough & is the worst part of the whole deal.

Good luck!!!