Well, I screwed myself over royally on this one. Bought the 95 S with a “bad” fuel pump. Brought it home, pulled the wires off the tank and plugged in my beeper. Turned the key on and about 2 seconds of beep - ok - power to the pump and no audible pump sound so gotta be a bad pump (or internal wiring). Pulled the tank, replaced the pump (and wire) and tested before pushing it back in - no power to the tank.
So I took the pump I removed and plugged it into 12v on the bench - spun like a banshee. I then ran a hotwire from the batt to the tank connections - new pump pressurized. OK… replaced the pump relay with a known good unit and no change. Jumper-ed 86 and 87 on the relay plug and pump runs full time. So I go to start the car. Nothing.
It will “start” but then immediately die. Did this 7-8 times. I then had the thought I had remembered that some ignitions with position specific key (key will only work when installed one way) so I pulled out the key, flipped it over, put it back in and the car started right up. Shut it off, restarted it and let it run for 4-5 minutes.
But then…
Quite happy, still pissed that I just did a LOT of unnecessary work but happy, I finished the install and went to drive the car back to the storage area.
Starts, and immediately dies. Flipped the key, nothin. Flipped the key, nothin. Just starts and dies. So my gut now has me thinking this may be a bad ignition switch since it dies after start and has no energizing power to the fuel pump relay, and that the test I did when I first started the project was a fluke.
anybody got ideas on what to check since the ignition switch isn’t something you can just swap out from another handy Jag?
You know what else you can’t easily check? Your fuel pressure. Perhaps the regulator has gone bad, or the fuel filter is stuffed. I’m assuming you can’t get it to run by starting it and giving it some gas.
I’m not sure what the condition of your plugs and coils are either. MAF sensor?
There’s a lot to look at before we can sentence your ignition switch.
think I found it. I’ll know in a bit when I bypass it and start/stop it a few times.
Inertia switch
I pushed it down even tho it didn’t look tripped and the car started. Next time I tried it didn’t want to start again so I held my finger on the switch and it started. Now I just need to bypass it for a bit and then find one local. Will update soon
maybe only part of the problem. IS was flakey on the bench so I replaced it with one from a known “formerly” running car. Problem persisted. Where I am at now is the O2 sensor relay. When I remove and re-seat that relay the car starts. Relay pins were highly corroded so pending cleaning the contacts in the relay socket somehow I may have to splice in a new/different known clean socket and see if that fixes it.
The wiring that has failed on many cars we repaired is the harness from behind the right side panel in the boot to the connector about a foot from the top of the tank as I recall.
I believe I have saved some of the non-melted ones of the same connectors that melt.
Another issue that once took months to locate is the heated O2 sensor fuse also on the right.
If you find that it is the pump I might have one I saved after I deleted Jaguars from my stable.
fixed -
how 'bout the O2 sensor relay. Sat down with the wiring diagrams and followed the money so to speak. Got down to the O2 relay, pulled and cleaned it (and socket) and everything works fine. I thought my 78 S was bad about relays running relays. This thing has it beat hands down!
white-base relay on right side under hood (center blue relay). Actually chased it down via an XJ6 go/no-go diagram then had to find it in the S diagrams and location. Noted on the XJ6 data as the O2 sensor relay