I have been chasing a fuel issue for a few years now and it confounds me because it keeps resolving itself. I believe I have the original fuel pump and relay on my 1998 Discovery 1. They look original, marked “97.” So on several occasions, I’ve apparently lost fuel pressure while driving. The car stumbles, runs weakly, and slows to a coasting speed. Sometimes it will just start going again after 15 or 20 minutes that I usually spend checking things but not finding any problems. One time I found the 15A fuel pump fuse had blown, but only that one time out of perhaps six or seven incidents. The latest incident, I did not seem to be getting fuel pressure even after hotwiring the fuel pump at the inertia switch. After I pulled the fuel pump, it ran fine on the bench. I reinserted it and everything runs fine.

My fuel pressure troubleshooting usually goes like this:

Check the fuel level.

Have a clean fuel filter in place.

Check for fuel pressure at the fuel rail Schrader valve. It may have some gas pressure from hot fuel, but if it “deflates” and will not re-inflate after switching the pump on, I know there is a pressure issue.

Check the fuel pump fuse. It is the 15A fuse under the hood.

Check the fuel pump multifunction relay. With the ignition on, if the relay is disconnected and reconnected the contacts in the relay should be heard clicking and the fuel pump should be switched on for at least a few seconds.

Check the inertia switch on the firewall. The switch should be pressed in flat.

Check for ~12V at the inertia switch plug. The relay may need to be disconnected and reconnected to check the voltage when it switches the pump on.

“Hotwire” or bypass the relay and inertia switch by running a small jumper wire from +12V to the connector for the inertia switch. The safest +12V source would be a 15A fused circuit. Connecting to the battery’s positive terminal risks melting down the pump motor or worse. Using this bypass method, the pump can be made to run continuously for diagnostics or to temporarily workaround a failed relay or inertia switch.

Check for +12V at the fuel pump under the carpet in the cargo space.

Check the ground connection at the fuel pump.

Pull the fuel pump and check the pump on the bench.

Verify the tank is clean.

I noticed that the fuel sending unit is sold complete, and that for the AEL models it is pretty expensive. Today, AB sells Eurospares brand and the sealing ring as a kit for $399.95. Partsgeek sells the same Eurospares part for $319, and the seal is about twenty bucks more. Rovers North Proline is $395. AB advertises price matching. Rovers North sells the Genuine version for $791. Partsgeek also sells an expensive Airtex version. Amazon sells the Airtex, and a Spectra version for higher prices, but can deliver next day, Saturday, and has free 2 day shipping for Prime members. Also, Amazon sells the fuel pump only, for $131.61. So instead of replacing the entire AEL sender assembly, the electric pump motor, pickup screen and plastic tubing can be replaced for considerably less. As long as the fuel level sender and the plastic on the existing unit are intact and working, it makes more sense to just replace the motor.

Now my dilemma is should I just put the carpet back and drive it until I have another issue? Should I replace the pump motor pre-emptively? Should I swap out the multifunction relay prophylactically? Is there something else I should suspect? CKP maybe? Darn gremlins.

 

Sorry I can't help, but I too will be awaiting an answer from wiser souls. My 98 came with an external fuel pump where the fuel filter is and I will be checking on the in-tank pump when other issues are settled. My fuel level gage is OK so I too hope to change just the pump motor.


Tom Rowe said, "AC Delco EP241 is the actual pump part number. Strainer is a Delco TS7", and another post said, "I can tell you from experience there's no difference between the non AEL and AEL pump, motor wise..." Checking just now, the pump is $54.38 and the strainer is $9.16 on Amazon.

 

THE ael non ael pumps may be the same, the problem is the ael sender is insane expensive, p o probly had a bad pump and went with a $20 jerrry rig insead of a $500 pump assembly

bivienna i do not know your miliage but would say buy a pump and sock and fuel filter see if it resolves your issue, sounds like your pump is overheating and locking up, cools down and starts going again imo

 

Yeah, thanks for the AC Delco EP241 part number. I was pretty sure there was a common motor part like that, but didn't know how to cross reference to find it.

At the end of the day, I figure both the motor and the relay are electro-mechanical parts that are only going to last so long, and then give up the ghost. I'm going to replace the motor since I can at least bypass the relay in a pinch.

The main difference on the AEL assembly is just the vent tube. It's insane when you consider how much more you have to pay for the addition of a plastic nipple. But I think most people will find their AEL assembly to be just fine and that it is the pump motor that needs replacement. Too bad the most common go-to suppliers like AB and RN don't list motors, but only list parts that completely replace the sending assembly.

 

No the difference on the ael is it has a tank pressure sensor that's the money, and that goes bad and shorts the TPS


Tell u what next time it shuts off unplug that extra plug on the fuel sender see if it starts, if so you need the sender

Helps to know your location

 

I am one whose level sender is apparently OK and whose pressure sensor is probably OK since I have no related codes, but that %^$#@ vent tube or the "anti trickle valve" are a real PITA causing it to take 20 to 30 minutes to fill the tank at a veritable trickle rate. I have to go to stations with newer pumps that can run more slowly than older pumps and I can't set the nozzle to run itself or it flows too fast and immediately shuts off. I have choice words for big brother government every time. I hope I will be able to find/fix the problem once I get into the original pump and before next winter makes fill-ups even more of a pain.

 

different vehicle same $$$ pump turned out it was a bad section of harness. every now and then the connection in the cable would heat up and drop out.
In my case there is a 20 inch cable that connects the main harness to the fuel pump the problem was in the length of harness.

 

phil i think the new sender resolved my slow fill issue, along with the pressure vapor valve issue at the ael charcoal cannister

harness is definitly something to look at, isnt there also a plug near the drivers side rear wheel well? iirc

 

yes, the cable from the frame to the pump has a break somewhere in it on mine. when it dies; if i wiggle that cable around i can hear the fuel pump pressurize and it will start back up.

 

thats just awsome lol yeah if i stand at the back of mine and someone turns the key on i hear the pump come on and prime the lines like it looses fuel from setting , car fires right off when starting though