I know this is an old subject but it just started on my 97 (68K) I changed the Crank Position Sensor after it started only because while I was removing it to clean it and it broke. The new one did nothing to improve the situation so I know it's not that. As you decelerate to a stop it stumbles but not every time and when it does if I go between "R" to "D" it will stall. this AM I started the car and drove my son to school and the 13 miles to work and no problems at all, drove the 13 miles home, no problems. Drove the 2 miles from my house to get him this PM and VIOLA it started doing it out of the blue. No OBDII codes are showing up as well as no lights on the dash. Just curious if this same situation has happened to anyone else and if so was there a pin-point solution. I've had this car for 2 years and put 15K on it and this just started out of the blue.

 

Welcome to the club. Mine just had the normal quick stumble for about a second while accelerating after turning a corner at very slow speeds. No CEL light or anything on the dash. It actually acts like a momentary fuel starvation. Hasn't happened in several weeks on short trip driving with an accasional 30 miler. It seems that every XJ6 will do it when that get older (125K on mine). 68K seems a little soon. Changing things is no help since it does it so seldom on my car. It used to do it more often. If yours is frequent you may have a chance at findint the problem.

Please keep us informed.

 

I think I'll put a fuel filter on it first then check the plugs to see if they need changing. I just wish it'd throw a code to give more direct guidance.

 

Spark plug brand and age?

 

Just looked, Champion and probably about 15K on them. They look good, ashy grey.
IMHO probably about 14K too many on them I'm curious why some Jaguar fans swear by them and everyone in Brit Bike circles swears at them. They are not even close to the Champions of old..I used to run a set of new Champions in my Bonneville (3 kicks to start when warm with new champs) let it sit at idle then quickly switch them out for NGKB7ES's and then kick it over (1 kick) and people would be amazed how much better the idle and throttle response was and how quick it started..it was that noticeable. I'm going to look for some NGK equivalent and replace the Champions, sorry not a fan of modern day Champions. I'm running NGK Irridiums in my TR-6 with and accuspark ignition and put them in my Lincoln LS w/sim COP set-up. I think I'm running them in my XJS as well.

 

Ok...so far, new Crank Posit Sensor...no joy. Tightened up all air intake elbow fittings, put in new iridium NGK's, coils have new gaskets and sealer around top fitment of boots plus liberal dielectric grease at opening of boots and installed new fuel filter. Hopefully it's gone but only miles and time will tell.