Car has original "Lucas" fuel pump and 75K on the Odo, anyone know the longevity of the original Lucas pump?

 

Pulled condensor thingy, no joy. Checked coaxial, no joy. Cleaned power resistor connectors, no joy. Siphoned 2 gals of fuel out of tank ( agitated first) no debris/water. I'm curious to see how it runs in the AM

 

JTsmks, I would try to help but I have a 4.0 with which, finally after two years chasing a bad idle is fine now. Keep at it, it will happen.
RagJag

 

Some good news....David Boger is sending me a TPS and ECU, so at least I can swap out and eliminate those two from the list AND if they check good I'll have a spare set (which you all know I'll need sooner or later!) If none of you have delt with David at "everydayXJ" your missing a gold mine of great parts at a great price. I've been doing business with him for some time and he is TOP NOTCH!!!!!

 

Ok, its getting weirder. I decided to duplicate yesterday, luckily its basically the same temp and PA outside. First off I went to jaguarfuelinjectionservices website and got his CTS chart, temp vs ohms. I pulled my plug and read out the sensor and it seemed to jive with the chart. Started the car right up and went on the same trip circuit as yesterday, no problem, car ran/idled fine (like yesterdays trip#1).

2nd trip 1 hour later car started fine yet idle was slightly, slightly mind you lopey and there was some pinging/clatter on acceleration like I'd expect on a super hot day with low octane fuel (car still ran OK but this is falling into place with yesterdays runs)

3rd trip.... and here's where it gets interesting, one hour after 2nd trip (remember I'm doing exactly what i did yesterday, also remember 3rd trip went south right out of the gate yesterday) temp gauge still just below "N" at the start...car started and ran AMAZING!! No lopey idle (not even a little like trip 2) no "pinging" upon acceleration, none, nada, ZIP. Car ran like a scalded dog on the same trip circuit as 1, 2 and yesterday by 3 it was in the dumps.....I dunno, I surrender!

I had my paper clip in hand to push it in the CTS plug when it failed to behave on start-up for trip 3 yet the car behaved amazingly and way better then just an hour before plus its actually warmer out. Go figure?.....stumped and dumbfounded!

Ok...trip 4 one hour after trip 3....still no problems, only slight pinging under hard acceleration.

 

Update, day three, still running fine. Leaning towards CTS but not the CTS but the plug/wires as that was "messed" with 3 times the day she corrected herself.

 

God find.

I reckon the CTS is fine also.

The wires about 6"?? from the CTS join up with the ATS wires in that black sleeve stuff, and a dry solder splice in there "could" be the gremlin.

Broken wires inside the CTS plug are common, and I think somewhere you have covered that?.

 

Hopefully "bumping" for another members benefit isn't frowned upon.

 

My '91 XJS 5.3L coupe (auto) just quit in a parking lot one day. After replacing the Crankshaft Position Sensor, It rens MUCH better, and the poor idling problems have gone away, as well. It acted like bad sparkplugs or injectors, missing and stumbling at idle. Now it idles very smoothly.

 

There's no CPS's on the Lucas ignition 5.3's. Good tip for those with Marelli ignitions though.