Just finished cleaning rockers and now on to another problem that I think has been intermittent for me, once in a while.

Barely made it home yesterday but car is now not starting, as I mentioned, previously, I would have idle stall intermittently, once in a while and because it was intermittently, it was difficult to diagnose but now that it's gone completely dead, it sucks but I think I isolated the issue but would like some help to confirm.
Starter turns but engine won't turn over even when pumping gas pedal.

Here's what I've done so far:
1. Starter was replaced earlier this year so it's not the problem
2. Battery/Alternator checks out at 12+ and 13+ respectively
3. I recently replaced the fuel pump, more as a precaution and potentially fix the intermittent issue.
4. Fuel filter replaced 8 months ago.
5. Check voltage at the fuse box, getting 12v
6. Check voltage at inertia switch, getting 12v and also did a short/bypass to confirm so the switch is probably not it.
7. Confirmed 5v on green wire on fuel pump for sensor
8. FAILED - no voltage on white/purple wire on fuel pump, this was turning on/off inanition confirming within 3 secs and no voltage still.
9. PASSED - ran voltage to fuel pump and pump runs.
10. FAILED - Fuel pressure test using loaner kit. No pressure. But when I manually turned on the fuel pump by running wires from battery, I was able to get pressure rise.

One more thing I did and not sure what to make of it. When I manual ran the fuel pump to the battery and started the car, it started up and ran for a few seconds then would stop. Not knowing much about this fuel system, I'm guessing that maybe it due to ECU responding to unplugged fuel pump connector but was thinking that car should continue to run while I had the pump on.

Sooooo....I am thinking that I have a bad pump relay??? Also, believe the fuel pump relay is not in the same location as the one shown in RAVE as I checked before when changing filter but went and head removed fuse and relieving pressure manually instead. Any help on fuel pump relay would be of help.

 

I think I found it...it was under the hood next to washer container.
Would like some input on my diagnosis before I order the part...thanks

 

Not sure about the relay... something simple to start with is the rollover switch, should be in the same area (firewall by the wiper fluid container). It's a round cover and a rubber top, press the button inside down and it should re-energize the fuel system

Also the fuel pump, how did you install it? the whole assembly or using the 20$ pump only method?

 

I believe I have ruled out the inertia switch. I pressed the button as well as took out the connector and put a short across the two. I spent this afternoon retesting everything and definitely not getting voltage on the white/purple wire for the fuel pump. I was able start the engine by temporarily running the pump using voltage from battery so I know the pump is good. I did confirm continuity on the white/purple and black ground back to the relay.

I replaced just the pump only and not the entire assembly and this issue is more than likely related to my intermittent start/idle issues. In looking at the electrical diagram, I think I was able to narrow it down to the relay or hopefully, it's not an ECU issue but will troubleshoot a bit more tomorrow to confirm.

 

Put vehicle year in signature

 

1998 Disco LSE, just added to signature.

 

It's not uncommon for the fuel pump relay to fail. If you have voltage on the Purple/White (Fuse F6 into relay) and not on the White/Purple well....that's a tell tale sign. I assume you've already ordered the part......? While I'm thinking about it the pump connector is a pigtail affair. There is another connector on left side of fuel tank that has a habit of becoming corroded due to wheel spray. Check it if you would to make sure it's not partially melted. That can cause the fpr to commit suicide before the fuse ever blows.

 

I went ahead and ordered a new relay. I went through with the multi-meter again and almost positive point where voltage breaks is at the relay. Again, I was able to start up the engine when I did a bypass and ran voltage to the fuel pump.

I will take your suggestion tonight and look at gas tank for the connector. It won't be the first rusty connector I would have to replace. The relay should be here today or tomorrow.

If anyone is interested, I can post some pictures of the inside of the relay. My curiosity made me take dremel and cut out the cover. Although it didn't solve my problem, it did help me understand how it works, including the mechanical switch that turns on for about 5-6 seconds when you turn on the ignition. I was able to confirm that was the switch that triggered voltage to the pump but I was not able to detect voltage on the white/purple going to the pump AND confirmed continuity from the fuel pump back to the inside of the relay. So something went awry in there I hope. This was how I was able to get the car temporarily running.

 

Fixed, it was the fuel pump relay.

ihscouts - went under the tank to see if I could see the plug you were referring to but the only one I found was what I believe the relief/breather line.