Well all sorted now,you were right Stan. Warped sump causing leakage,oil change,new sump,the metal more expensive but worth it,new switch gear in box.Hey presto beautifull silky smooth changes,instant kick down.Price was £420.00 all in.
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Just thought I'd let anyone interested that the problem is now solved. It was the ABS sensor in the front left wheel bearing.
Luckily I managed to locate a brand new part on Ebay for £59.00, which was a much better deal than the £400.00 Jaguar wanted.
If you are looking for the same part, drop me an email and I'll try and help.