V8 disco starving for fuel?

[3 Sisters]

Stupidly took my 91 disco into a mechanic to get a discount filter change, got it back, and it ran fine on LPG, and was fine on fuel,then when out in the middle of nowhere(Mt franklin Brindabella MTNs near ACT), it started starving for fuel, then 5minutes later would pretty much only idle, as soon as I pressed on the accelerator it would bog down and I guess starve for fuel.
It'd run fine on LPG, so I'm guessing the mechanic may have done something stupid when changing the fuel filter.
So I turned it around and started a 10km decent into the valley, I tried doing some key bangers by turning off the ignition while rolling in gear, then turning it on again, to see if I could clear it's throat(yep you guessed it, my mechanical knowledge is limited, and even worse when it comes to fuel injection)to no avail(wouldn't even bang).
I couldn't locate a fuel filter anywhere on the car(it was raining and muddy, so didn't look near the tank), is it in the injector area, near the tank, or where?
Anyway, I was hoping that by descending in gear it may clean it out, and low and behold it did, luckily as I was a long way from anywhere(parents farm, brindabella valley).
Due to it not idleing that well and stalling easy. Whilst descending I was bump starting it on fuel at every decent corner so I had power for the brakes, and steering, when a hill came I would switch it to LPG , and bump start it to get up(LPG light was flashing empty, hence why I couldn't just use it).
After two days rest(with just a few KMs driving done)I set off home, on the way back up the big hill it only had one or two misses when it starved for fuel for a second.
I've put an injector cleaner in the fuel from a petrol station(please don't cringe), and driven it all the way back home from ACT(350km), but it still has a little hic up every now and then.
So, before I take it back to the mechanic, is there anything I can check? as I'd rather not take it to the mechanic again.
Could it just be bad fuel? Some water in the fuel, should I put a cup of metho in the next tank of fuel(I'd rather burn up all the injector cleaner first, but I'll ad metho if it gets bad again, as it's raining a bit here now).
I'm guessing it wasn't just the elevation, as I live in Katoomba(MTNs) and it runs fine, normally, and I doubt the elevation is much different where I was and it still has a brief starve every now and then.
The mechanics also changed the air filter, do I need to check if they left a cup of sugar in there or something?
On a side note, My car normally pop pop pops when engine braking, I'm guessing it's running a bit rich, but does it on LPG or petrol. It only has the rear muffler, I'm sure that makes it a bit exagerated, but it wouldn't make it pop would like it was running rich would it?
Please don't be led astray by my ideas, I'm just guessing it's fuel delivery issue in both cases.

[ohleaky1]

Is the 91 fuel filter in the same spot as 94? if it is! look under the driver side rear wheel arch and you should spot it no prob,s.
Some take tyre off to get to it easier, some dont....

[3 Sisters]

Is the 91 fuel filter in the same spot as 94? if it is! look under the driver side rear wheel arch and you should spot it no prob,s.
Some take tyre off to get to it easier, some dont....

Yep, it's there, thanks. Should the crimped over end of it be at the front or rear? Would it work if it was on the wrong way around? Can it be put on the wrong way around?

[ohleaky1]

more rounded end facing rear of vehicle.

[PhilipA]

They usually have an arrow on them which points in the direction that the fuel should flow.
Regards Philip A

[MacMan]

I had a little chuckle about the key bangers. You'll never be able to do them in a healthy injected V8 because the injection is shut down when the ignition is turned off, and the LPG in your case should have the solenoid turn off at the same time. :p

I know tailpipe ignition in my Disco is VERY loud but I only know because I had a coil failure.

[3 Sisters]

I had a little chuckle about the key bangers. You'll never be able to do them in a healthy injected V8 because the injection is shut down when the ignition is turned off, and the LPG in your case should have the solenoid turn off at the same time. :p

Thanks, that explains that then. I was wondering if it was just not getting enough fuel.

[bee utey]

Next time it does it, if its still idling, (gas or petrol) pull over and listen for the EFI fuel pump. You might have to be near the fuel tank. If its faulty it will first be intermittent before stopping completely and you won't be able to hear it any more.
Ask the mechanic if he inspected the old filter. You should always hold your old filter over a clean tin to see what is in it. Anything in the filter has been through the pump.
Sometimes the electrical connections to the pump can get grotty and melt, anywhere under the car or in the tank assembly itself.
Sometimes banging a petrol tank will temporarily restart a pump on its last legs.
Banging in the exhaust (with closed throttle) usually occurs with air leaks in the exhaust, although having only one muffler would do it. Air gets in and causes lean mixtures in the exhaust which explode easily.

[3 Sisters]

Cheers bee utey, I'll check the pump if it gets bad again.
There's a tiny hole in the pipe/muffler, I'll weld her up, and see if that helps.

[Flybouy75]

I have just went down to the shop, and had the engine just stall at 60kph, tried to restart, but refused.

I have replaced my fuel pump a week ago, I can hear the pump, when I switch the ignition on and off, I have done a fuel filter today, but suspect the MAF..... thank's to the good folk's here.

This is happening hot or cold, but seem's worst when cold, I got it restarted by removing the MAF plug, started straight away, and ran fine, just a little rich, I think, so Im pretty sure I had narrowed it down to either the MAF or Fuel filter, because, it was like it was out of fuel, but I have a new stepper motor and all the other quality Lucas parts for ignition so I think I have the culprit....... but I may be wrong.

Hope it help's.... it can be so frustrating chasing these gremlin's not to mention expensive, I fortunately have new MAF on the way, when it get's here, I'll post my result's after the MAF

Cheer's Shane

[It'sNotWorthComplaining!]

I used to run my Disco on lpg all the time, then I found the petrol side wouldn't work. I pulled the injectors out and found the pintals has disintegrated, replace the injectors and problem went away.

Years ago I had a problem on a trip Melb to QLD in our falcon , thought I'd run some injector cleaner through on the trip, I over dosed it and found I had problems similar to yours. I replaced the fuel filer and all was ok again. The injector cleaner must have cleaned all the crap in the petrol tank and sent it to clog up my fuel filter.

[3 Sisters]

Hmmm, well this problem is back, won't run at all on petrol(well it will down a hill, but not really). I'll run it down some hills on monday, see if that clears it again, but there's no real big bumpy hills nearby like I used in the first round.
So if it went and returned, does that give anyone any clues? I've tried to check the wiring but it goes all through the body, and there only seems to be the one fuse in the line inside the car with the other fuses. Could the fuel filter that was installed have a flake in it, or be dodgy?
How do you clean the gauze filter in the tank?

[mike 90 RR]

A link for you ....

http://www.aulro.com/afvb/discovery-1/94418-95-v8-running-bit-rough-4.html

Basically ... recheck your Petrol filter ... see what comes out of it (from the fuel tank side)
Have a read of the Answer "post 33" ... Then read the whole thread ... see if there's something familiar for you

[mike 90 RR]

Also .....
When they install a LPG system,they splice a wire into the EFI wiring harness
Try to find where they joined / spliced in, & check that the connection is not faulty .....

Mike

[3 Sisters]

Okay, so I've changed the filter again, and it still starves for fuel. If i put it on petrol going down a hill, it will have a slight surge in power when I back off from attempting to accelerate.
So my possible problems could be any of the following.
Wiring.
Fuel blockage.
Fuel blockage at tank gauze(how can I clean this? Compressed air up the fuel line?).
Fuel pump relay.
Fuel pump.
Anything else?
How can I diagnose any of these problems without replacing all parts?
Can I disconnect the fuel line at the filter, and turn key to power to see if the pump pumps?
I'll try get hold of a voltmeter to check the wiring.
I drove down many big hills with it on petrol trying to clear it, but it didn't work, and I was wondering if I was hurting the piston rings or anything else from lack of fuel to lube.

[LandyAndy]

May be worth checking the fuel pick-up in the tank,if its contaminated/blocked it will cause these symptoms.See if anybody with experience on the same vehicle agrees.I have had the same issue on Series landies and Falcoons.
GOODLUCK
Andrew

[bee utey]

Quite a few D1's I've come across melt the plug connecting the pump on top of the petrol tank. It heats up when running and then disconnects. If you get the plug off the tank connector look inside it for a brown patch around the connector pin. You would need a new rear harness section with plug and pump housing to fix it.

I hope the round cover in the middle of the boot floor is accessible for you (under the carpet). If it is you can easily remove the whole pump assembly and check the pressure hose to the outlet for splits etc., also the inlet filter screen. I hear that adapting a Bosch VT Commodore pump kit is the cheapest option for a new pump and filter.

Another customer had the same trouble with the plug earlier in the same harness, just above the rear muffler. The earth connector had fried and I just soldered the cables together after removing the plugs. In his case the petrol gauge also read empty.