Not sure what is going on with it. It’s running a little rough anyway but about 2k RPM it vibrates a good bit like it has 2 cylindersdown or something. I thought it might have been a drive train issue but I can throw it in neutral and it goes away. Then while I’m still rolling down the hill rev it up to about 2k and it feels just like it did when it was in gear. Also I can just rev it sitting still and it vibrates/misses.



The crazy thing I’ve found out is on a full tank of gas it runs quite a bit better than it does when it gets on a 1/4-1/8 tank. Also it seems to idle higher on a low tank so it makes me wonder if it’s going lean.The truck was down for a few years but I’ve run quite a bit of fuel and gas treatment/injector cleaner through it since I’ve had it running so I wouldn’t think it could still be bad gas.



I’ve searched a good bit on engine running rough at a certain RPM but the only answers I’ve turned up were for a diesel land rover (bad injectors). I’ve given it a tune up, plugs, wires, distributor cap, button and fuel filter.



So what would make it run better on a full tank? Pump getting weak? Crap in the tank?



Thanks in advance, Paul

 

Oh yeah and it’s a 1995 3.9ltr

 

Have you looked in the tank (removed pump) to see if there is debris on the bottom?

 

No but from doing some searching on “why does my car run better when the tank is full?” it looks like I need to pull the pump, clean the tank and replace the pump.



Does the disco 1 have a trap door for the pump? I can just cut the carpet and get to it?

 

Pull up the rear cargo mat/carpet/padding and voila'! There in all it's glory is an access cover over the pump. Usually the pump screen is coated with sediment like cement. If that's the case what little is still open on the screen becomes blocked with loose debris in the tank. I hope that's the problem because your issue is not common and would take some serious detective work to find it. That's why you wont find posts, it's not a common fault.

 

If you don't find a cover you have an early built 95. 94's I believe don't have the access cover. Idk if that's entirely true.

 

I bet you are correct about this.

Damn I hope it's there, I do not feel like dropping the tank. I can't understand why any auto maker would not install a cover. They can't save that much by leaving it out.

 

You are lucky the whole assembly for yours is cheap mine is big money new for what it is, should be a pump and sock available at auto zone to rebuild assembly on the cheap part # are floating around here

If it is same setup inside as mine I would be suspect of the crappy plastic hose that runs from the pump to top of sender that can be replaced with fuel injection hose and fuel injection clamps, must say fuel injection on it, special

 

Napa carries everything to do a swap too. Here's a good write-up and although it's for the RRC it still applies; fuelpump

If you look down toward the bottom it has non-OEM replacement pump motors through another link which used to be for the D1 as well. This is the site I used when I first bought my Disco.

 

Looks like I can replace the whole thing for 80 bucks

As cheap as this is I might as well replace the whole thing unless you know of a reason I shouldn't use this pump.

Land Rover Discovery Range Rover Electric Fuel Pump Allmakes ESR3926E | eBay


Edit: oh and thanks for the info guys.