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Hello everyone,

This is my first posting on this bulletin board.

My beloved 1994 4litre XJS will not start.

I have changed the spark plugs, distributer cap and rotor arm. The leads are only about 6 months old and I have hardly done any miles since I changed them.

When I try and start the car It is as though she is trying, but not catching. I have put a strobe light on piston 1 and on the coil and can see that the light comes on as expected showing that there is a spark.
I have removed the fuel feed to the injectors and can see that there is plenty of fuel coming up. When I took the plugs out I could see that they were damp.
I am at a loss as what to look at next on such a complicated car (I also own a 1961 Mk 2 and my wife owns a 1959 MGA). I did notice that the car was starting to run a little lumpy a couple of weeks ago.

If anyone could give me an idea of what else I might check or something that might be giving me problems, I am aware that there are a number of EMUs around the car, and I wonder if it could be one of these.
I hope that you can help me.

Garreth

Hi Garreth

Welcome to the Forum and I'm very sorry to hear it's under such circumstances, hopefully between us we can get your beloved car back on the road soon.

NB Are you absolutely sure there is a spark at the spark plug?

I had a very similar problem with my 89 3.6. It turned over, had a spark, had fuel but just would not start......in fact it barely fired - more of an occassional pop!

I suspected the crankshaft sensor. This is mounted at the front of the engine above the crankshaft and by monitoring a larger tooth (than the others) on a wheel bolted to the end of the crank going past the sensor tells the engine ECU the position of the crank and hence gives the ECU the timing information it needs for the engine to run.

I had the car recovered to my local specialists and in fact it turned out that the ignition ECU module had gone Kaput. A secondhand ECU was fitted and the car started straightaway and ran perfectly thereafter.

It is quite possible that either of the two above faults is the problem with your car - the question is how can you get it fixed? If you have a local specialist that you use then I would ship the car off for diagnostics and rectification.

If you do your own maintenance perhaps another member can help with a substitute sensor or ECU to test by elimination. In fact I don't think the crankshaft sensors are too expensive and they ARE prone to failing without notice. I'll check out the price and come back.

Done that.........see here, (Item No 17)


http://www.jaguarclassicparts.com/webap ... gory=20993

As you can see they vary from £38.50 to £67.13 dependent on ENGINE VIN Number and all are showing as available.
These parts can be ordered through your local Jaguar dealer and if you show your JEC membership card you will get discount - typically 10-15%.

GOOD LUCK and do let us know how you get on

DH Dove