It happened again my daughter called and said her 1999 Range Rover 4.0se just shut off and would not start. I got there as all Dad's would, and opened the hood took the rubber tire valve cover off the fuel line at the front Pass side of the fuel wrack and let out a burst of air that could have filled a basketball. I then told her to try it and off she went ? Has anyone run across this problem or read how anyone fixed it ? I have checked the pump, lines, pressure regulator (FPR) and most of the electronics but this ghost keeps coming back. I am going out today to get all new Vac. hose and a new Fuel pressure gauge just to be sure it's 35psi. I used the GEMSbyPoole.pdf as a guide but still have a problem. This problem happens once a month and always at different times. It is also hard to start sometimes and takes three tries to start (sometimes 4). But like any 17 year old she only tells me after the fact and I can't get it as it's happening. Not sure what it should sound like when the hood is open and you turn the key to run (not cranking) ? Sometimes there is clicks, buzzes and other noise ? not the same each time.


I changed GAS to 93 oct. - spark plugs-wires -belt -1fuel filter the pdf said there is 2 but I didn't get a chance to look for the 2nd one yet and didn't see it in line so it might be in the tank (maybe a screen on the fuel pump)

 

Hola--Que tal!
A suggestion! Perhaps the hiss of a gas you have observed is in fact fuel vapour caused by boiling fuel dormant in the rail.

The system by your description suggests a Gems engine fueling system hence a return of pump excess back to the tank and regulated by a PRV on the rail and over pressure controlled by a vacuum line at the back of the plenum chamber on the drivers side. The excess fuel helps keep the fuel in the rail from boiling and gives ample fuel delivery for acceleration upon demand

What might be happening is that the fuel pump is going down or the driver relay in the engine compartment is intermittently unlatching.
The first thing to do is get a gauge on the rail and read the pressure should be 2.2 bar regulated (that's about 34 psi ) and if you pull that control hose off while it running the pressure should bounce up to near 40 psi

The first thing to look at is the fuel filter mounted on the frame just f'ward of the passenger's side rear wheel. Often neglected it gets plugged up and restricts the fuel flow giving the symptoms you have explained. This filter holds particle/dust contamination down to 20 microns so it gets plugged up very easily in dusty conditions when you successively fill the fuel tank.

If the fuel filter has been run for an excessive period totally plugged up the relay might be in poor condition since it will be subjected to amperage pull in excess of 5 amps and the pump struggles to pump fuel through a restriction.
Once changed check the pressure with a gauge and once related pressure has been attained shut the engine down and observe the pressure gauge reading it shouldn't drop more than about 5 psi over the first 5 minutes.
Any more than that and the pump might be shot and you will need a new one!
Hope that helps and you can show your daughter that Dad's knows best.
I have three all driving! OMG
Cheers T/V

 

I got a Fuel pressure gauge and connected it to the rail. The PSI on the rail was a solid 20psi ? never went higher or lower while key was on ? (running and off) I checked the FPR (small Dia) at the rear of the intake on the US driver side with a vacuum gauge/pump. The line was somewhat dry rotted but the diaphragm held -20psi ? I changed the hose anyway. I also found a line on the cruse control diaphragm T disconnected so I replaced it. The truck seemed to run smoother but did not road test as the sky here opened up and I had to stop and swim for cover. I changed the fuel filter with an aftermarket filter that might not be good ? The factory filter was rusted on solid, so I had no choice but to cut it off and put an inline filter. Can you suggest a filter that might be less restrictive as the line pressure was only 20 PSI max (the gauge is a cheep one and could be off) I really enjoy the easy fix. I was shocked when I changed the belt and the fan shroud just un clipped and moved out of the way. I wish US made trucks and cars put the mechanic in their design. Ever change the starter on Cummins Diesel with the 3/4" 12point bolt pinned between the base of the block and behind the 40+lb starter you need a 20" offset extension on your 1/2" air gun and hold the starter up with your forehead

 

OK!
Sounds like the fuel pump is shot. The system must develop the 2,2 bar 34/35 psi to work effectively since for instant throttle response the system must then react to 40 psi to get acceleration response.
Going back to your original post the vapour you observed is fuel boiling in the rail due to reflected engine heat, and lack of flow through the rail over the PRV and back to the tank.
A new pump is best obtained from a place Like Atlantic British as it comes complete with seal. The pump is rare due to obsolescence these days so it is expensive at about $600.

I have devised a fix by using a Chev pump but is not a direct fit, PM me and I can give you details, it works!

In many cases that in line filter you struggled with is the culprit as it often gets neglected and plugged up. Consequently the fuel pump overheats trying to force fuel through a restriction. The fuel filter is the same as Chevrolet applications and easily obtainable from most parts stores.

In cases where the filter and pipes have to be chopped out as in your case , the repair is use 8mm compression pipe fittings and new ends. Now easier said than done! You might have to go looking for a good hose/connection dealer to locate them being metric. The pipe ends I usually scavenge from a wrecking yard, "hacking and whacking" the filter and pipe lengths out of a wrecked LR.

The are two types of fuel pump for the p38 and are similar to D1, since the one you are working on is late model with advanced evaps it will have push on quick detached hose fittings and two plug in connectors and a small hose for a vent diaphragm on the top. All of this can only be accessed only by dropping the tank .
As you draw the bucket style pump cartridge out there will be a seal on the tank lip which should be replaced. For ease of fitting located it on the lip put some engine assembly lube on the seal then feed the pump into its location observing a locating tab on the right side. If you roll it out or damage it undetected you will get a CEL due to evaps issues so beware!
Other than that I would change the fuel pump relay and fuse found in the engine compartment box. I bet with all that pump current draw they too have suffered.
Just for info on the rail above the injectors you will notice a black sensor/socket! That is the fuel temp sender and the readings it gives out makes the PCM adjust the fuel injection duration according to the fuel temp in the rail.

As for Cummins engines--yes we do a fair amount of diesel work in my shop; mostly Sprinter vans. I have a young female mechanic who does the fine work and young gringo as my "top gun" on diagnostics, although I can make her grunt doing t/cases on Landrovers !!
I haven't asked her to do a starer on the of the "big boys" --yet!

Although for trucks and the heavy stuff I have Latinos exclusively. Come (well trained mostly from Mexico) and do excellent work.
Amistades
T/V

 

I already changed the fuel filter and cut it off and open to see if it was plugged. I didn't find any junk in it but I think the one I replaced it with might be too small ? I had a few rolls of different sized fuel line and used the closest one I had but will probably go get some metric line. She came home yesterday with a cracked windshield so I have some time to do the fuel over when I setup a new windshield. The thing that is driving me crazy is it runs great for 28 days then just stops once and will run great again once you get it running again ? I have a bag of relays from 2 fuse boxes. I will have to hunt and find which slot is the fuel pump. The gauge I used was bought from a junk tool store so I don't really trust the readings. My tools were stolen during Sandy a storm we had here in New Jersey. I am not sure where you are ? I had about $30k in (un-insured) tools (Snap-on, MAC, Matco) but when we evacuated the thieves didn't and now that I am retired on disability I can only replace what I need and not all the special tools I had and even made to make life easy. I am not sure if I am ever going to get this running I have to do the work myself and we are still hurting from the storm here. They say they built back the shore but there are still hundreds living in campers. My mother in law is 1 of 3 that moved back in in her area and she had 40 neighbors. Thanks for the help. If you have a link to the fuse box layout send it please, I will look for a little while but can't tell if I have one.