1997 Discovery 4.0

Started two weeks ago. It seems that it may have started right around the time of having run out of gas, but I honestly can not remember because the running out of gas was first thing in the morning right after early AM start of vehicle (see more details below). Pretty much the same pattern now. Will start fine in the morning. Drive it 15 min or 2 hrs does not matter. Stop and immediately try to restart it WILL restart but struggles a bit, like fuel staved. Stop and let sit for 5 or 10 minute, will not turn over. Sounds fuel starved. Could try 8 – 10 times. Sometimes very close to turning over, but stutters and bucks like a was running out of gas and within 2 seconds dies. I have tried spraying carb / choke cleaner in the intake hose and it will run for 3 -4 seconds until it burns through that stuff and then dies. Seem so fuel related. Wait around 4 hrs (seems like one time waited 2-3 hrs and other times 5-6 hrs) and it will start one the first go around, but with some struggle. If it does not start of the first attempt, forget it, it will behave like before I waited so long.

Was told that the fuel pump, when key is turned all the way over before trying to start, should have a hum to it. Did so, got out of the vehicle and put my ear down behind the vehicle near the fuel pump and did NOT hear a hum so it seems it is the fuel pump. Weird though that vehicle gets the fuel it needs first thing in the morning and runs completely fine when it does start up in the morning. No stalling or stopping with such symptoms once the vehicle turns over and starts and runs. Changed plugs and wires this last summer using Champion plugs. Checked plugs now and no fouling.

I was told to first try a fuel filter as running out of gas may have caused sediments to deposit. I have NOT done so though I have one ready to put in. Told that without hum that fuel pump should be replaced. I have NOT replaced the fuel pump though I bought one and have it. I am a novice and don’t want to jump in over my head. It seems to me (a complete novice) that fuel filters and fuel pumps should be more along the lines of working or not working or should not follow such pretty predicable patterns as this. It almost seems as though there is some sort of sensor issue. The sensor is fine to allow the vehicle to start within 5 seconds of shutting it off, but detects something if it has been sitting for several minutes right after having been run. But allow the vehicle to sit for 4 hrs or overnight and the sensor “clears” itself and vehicle starts normally.

Please help. Thanks.

 

To clarify. If the starter engages and you hear the engine trying to start, then it is turning over. If the engine does not rotate when you try to start, then it is not turning over.

That being said, the pump is in the tank and, believe it or not, the fuel cools the pump. With no or low fuel, the pump can overheat, causing it to stop functioning properly. You may have a pump that works fine when cool, but after running for a while, will not pump adequate fuel pressure to restart the engine. Hook up a fuel pressure gauge and see what the pump is doing. Or, spend $100 and replace the thing without any diagnosis.

 

Thanks for the clarification. So I would say that indeed it does turn over.

Since I bought a fuel pump, I will go ahead an install it. Any awesome links to fuel pump installation for this vehicle that has stuff that a manual does not normally cover.

Thanks very much. I will work on this and report back.

 

https://landroverforums.com/forum/sh...ight=fuel+pump

Also, download the RAVE if you have not done so as of yet.

 

Go ahead and replace both the fuel pump and the fuel filter. The fuel filter is relatively easy and cheap. Both replacements are pretty straight forward.

Be sure to depressurize the system first. You may have some corrosion on the lines and fasteners to deal with as well. Review that link in detail first.

Don't allow it to run empty again, I usually fill mine when it gets down to a quarter of a tank.

There is a Schrader valve on the fuel rail wherew you read the fuel pressure with either a fuel pressure guage or a dial type tire guage. Mine sprung a bad leak when I did it with a tire guage.

Do a search and you will see what I posted about that.

 

I took up the carpet in the back to access the fuel pump plate in order to remove the fuel pump. The plate is secured with screws that have square holes. I have flat blades, philips, star bits, and hex, but nothing that is square and Autozone does not have any bits for this. What kind of bolt is this and how do I get these bolts out now? Thanks.

 

Go to a hardware store. They come in 3 different sizes. But you can get them for a buck each to use in a impact driver or drill.

 

Probably s-2 size.

 

I have not gotten to the pump replacement yet, but I did change the fuel filter and I put one bottle of Lucas fuel injector cleaner and a bottle of Lucas deep fuel system cleaner into the tank in case I am dealing with gunned up injectors. Well, it is different now. I turn the key and it starts, all be it sluggish and will run for 1 to 4 sec. It either dies like someone pinched off the fuel to the engine or if I press the accelerator is dies and dies immediately. After I do this two or three times it become harder for it to turn over and sometimes does not. Tires the battery out to. Wait a minute or two and the cycle can be repeated. Ran through this about 8 cycles, left for two hours, repeated it. It seems so close to want to run. It is getting fuel somehow but why does behave like this. Is pump really not working if it seems to get enough fuel for a few sec?

 

Get a fuel pressure tester and check your fuel pressure.

Test the old pump's pressure BEFORE you pull it out. Then test the new pump's pressure. Then you can compare the readings. If the new pump does not fix your issue, then you will at least know if the old pump was bad, good, or on it's way out the door.