My first guess would be fuel starvation. Fuels pump(s) EFI, ECU.
I remember I had a BMW do that and it was the ECU.

 

Runs if squirt startung fluid. Should have tried that first. Currently draining tank to replace fuel filter. I know pump runs and connected because when key to on flow increases.

 

Switched with TPS from my XK8. No change.

 

Video of start.
Edit: won’t upload

 

Replaced fuel filter. When draining by gravity turned key to on and flow increased so thought pump 1 good. New filter and still no start. Jumped fuel pump 2 and ran fine. Didn’t know a pump could partially fail. Will be dropping tank again.

 

Wondering if both pumps activate when key turned to “on”. I’ll pull pump 1 relay and listen.

 

Only pump 1 squirts for two seconds.

The first time my pumps went out, or I should say replaced because it was only pump 1, it was a slow process. It began with hard starting, but would run fine after wards. The hard starting continued until the engine wouldn't start at all. I guess each pump can fail in its own way.

Kind of glad it wasn't one of those two eBay TPS's, but that would have been a lot easier to R&R with the rebuild between the two R's.

 

Nope, both engage on start up. Tested by pulling P1 relay. P2 relay clicks, pump buzz and runs for a couple seconds. Pull P2, P1 in, clicks, no buzz.
In hindsight based on symptoms should have figured out.

 

Thanks again for the TPS. When I go on long trips I take an extra TPS and MAF

 

Take a medium gauge jumper wire with blade type connectors end to jumper the fuel pump relays 3 to 5 , this substitutes the control function

With replaced pumps you can still get bad pumps out of the vendor and seems to be the check valve from reading others , nature of the beast

 

That's interesting; I even ran that through AI so I wouldn't have to do a forum search.

 

Looks like the robots need a few more years to take over.

 

Yer welcome. My car eats PPS's more than TPS's, so I carry one of those on long trips, along with a small hydraulic jack and of course, the tool box. I now have three MAF's in the spares area (laying around somewhere); one is bad but I don't know which one.

Edit: I should have said "When I take the Jag on a long trip." Those are limited these days to just going over to San Francisco to visit my buddy that has His and Hers -100's. His is hot rodded, hers is in concourse shape.

 

Next time I'm in a salvage yard I'll lookfor a PPS.

 

Just pull the complete TB.

 

You were right about it only being one pump. It’s pump 2 (bottom relay in boot box).

 

That's interesting. Everything that I've read says pump 1 does all the work and pump 2 is there when the ECU decides pump 1 isn't keeping up with the demand for fuel. Have you looked around the relays to see if there's an extra wire running from the pump 1 relay to the pump 2 relay? Maybe a previous owner did some mods in there. Or, the ECU thinks pump 1 is still out so it has switched to pump 2.

 

No wiring visible from top. With tank in before hooked up lines checked. Both relays in fuel flow when key to on. R1 out / R2 in fuel flow. R2 out / R1 in nothing. Jump pins at R1 fuel flow.
Also put in new fuel level sender. That was pricey. Now have gauge from F To E instead of 3/8 to E.

 

That's how I understand it except Pump2 does the pre-start priming so it gets a bit of use.

 

Sounds like everything is working now whether it's #1 or #2, so you don't have to worry about it for another eight to ten years. Yea, those senders are pricy. The last time I bought one, I think it was six years ago, it was $250-ish from Rock Auto.