List ignition. Help

[Doherto]

Hi everyone, I joined this forum recently having sold my Mk2 and bought a Japanese import XJ40 in mint condition with 12k on the clock. I have now done about 400 smooth trouble free miles until today. We are travelling around the Yorkshire dales for the weekend staying at Nidd Hall near Harrogate. On the way her after about 60 miles I felt the engine sort of miss. I thought she messed up with gear changes in the auto box as it passed within seconds. However a few miles later she died, no revs no engine power at all. The battery light and the oil light illuminated and we rolled to a stop. I switched off suspecting the alternator or battery but as the volt metre always reads 13.2 volts and the oil pressure when she is hot reads 50 plus I was baffled. To test the battery I tried to start her and she fired up immediately and then ran for 30 miles to the hotel without an issue. Therefore I am 100 miles from home and not sure if I will get home. Only check so far has been battery terminals which are ok. I guess engine earths are next but this post is to ask if anyone has seen this before and or anything easy to check in a hotel car park. HELP.

[Doherto]

Hi everyone, I joined this forum recently having sold my Mk2 and bought a Japanese import XJ40 in mint condition with 12k on the clock. I have now done about 400 smooth trouble free miles until today. We are travelling around the Yorkshire dales for the weekend staying at Nidd Hall near Harrogate. On the way her after about 60 miles I felt the engine sort of miss. I thought she messed up with gear changes in the auto box as it passed within seconds. However a few miles later she died, no revs no engine power at all. The battery light and the oil light illuminated and we rolled to a stop. I switched off suspecting the alternator or battery but as the volt metre always reads 13.2 volts and the oil pressure when she is hot reads 50 plus I was baffled. To test the battery I tried to start her and she fired up immediately and then ran for 30 miles to the hotel without an issue. Therefore I am 100 miles from home and not sure if I will get home. Only check so far has been battery terminals which are ok. I guess engine earths are next but this post is to ask if anyone has seen this before and or anything easy to check in a hotel car park. HELP.

[cafcpete]

Oh sorry to hear of your problems.
What year is your car?
There is not a great deal you can do in a hotel car park, but maybe check the fuel pump relay. If you can find a parts shop it could be worth getting some electrical contact cleaner and give the contacts a good spray. It might be worth swapping it with another, non vital, one.
There was a TSB for this
http://www.jagrepair.com/images/TSB/TSB ... 0Relay.pdf
I think the relay is in the boot but others will know better than me.

Some other things are the crank position sensor may be starting to fail (not easy to check in car park), and oddly the transmission fluid level.

This is a helpful link to Haynes manual and other files.

https://www.mediafire.com/?hx8bttsy4kxxr

Good luck

[Doherto]

Cafcpete. Thank you for your message. I didn’t have much choice but to take her out today and see what happens. And she ran like a dream as usual if it was my Mk2 i’d Have my tools and a metre with me and the knowledge to sort it when whatever does fail but being new to the XJ 40 I am going to have to keep my fingers crossed and my phone with the green flag app charged. Hopefully you will not hear from me until I get home Monday evening after which I will get her plugged into the limited diagnostics I believe are available and discuss some pre emptive changes of parts my local independent jag specialists suspects Thanks again.

[cafcpete]

Hopefully just a blip and you will get home in one piece, but I think, when home, I would be changing the crank sensor as its cheap and does go wrong at just the wrong moment lol

[Doherto]

Hi, managed to do the tours around the dales we had planned, 200 miles plus, and arrived home without any more issues. Have spoken to Steve, our JEC Manchester region Jag specialist and so as previously suggested, I am ordering a new, Jag, Crank Position Sensor and fuel relay and for now and keeping an open mind on changing the fuel pump at some stage. Even though my 40 has only done 12,000 miles I appreciate that all the parts are 30 years old and so I will have to accept some minor issues. She is running like a dream though having now warmed her up with 800 miles recently. Thanks again Cafcpete Tony

[Andy P]

Hi Tony,
Glad you got back safe and sound and had a nice weekend touring after a worrying first day.
Hopefully they were just lack of use issues and the measures you are taking should prevent it happening again.
Enjoy your car and take care.
Andy

[Doherto]

Hi All, just a note to close this thread. Having changed the Crank Position Sensor for an expensive Jaguar part I managed about 200 miles before the fault repeated. (on the Hardnot and Wrynose passes of all places) I was carrying a new Fuel Pump Relay which I installed and have not had any problem since and have covered 700 miles. The old relay contacts were well Oxidized as were the female spade connectors in the plug. When back home I have now also replaced the plug and spade contacts and am confidant that the problem is cured, and she's running like a dream. I have sent an article supported by pictures which may appear in the club magazine. Thank you to all for your inputs. Happy motoring. Tony D

[cafcpete]

Glad you have found the problem and let us all know.
As that relay had corroded contacts, it might be worth your while going around all the others and giving them a good spray with electrical contact cleaner!

Take care, Peter