on the temp switch at the rear of the r.h. water rail. EAC3762
not the gauge sender at the front.
Is one of the wires an earth as one is black and the other looks like black with a grey tracer, if one is a earth it would mean I could earth somewhere else and not cut into the harness

 

What are you trying to do with it Rex? If you want to disable the 15 minute enrichment timer, you just disconnect the switch and tie off and insulate the wires.

 

just want know if its an earth that's snapped off in the harness if it is I can run in another one and wont have to cut up the harness.,
its black and if it is does it go under the throttle vacuum control switch?

 

Rex
Black is always earth on the XJS. One way to test it would be to earth it, start the car cold and then un-earth it while running. It it is working OK, then you will hear the engine note change as the enrichment stops (the equivalent of the switch switching off when hot).

 

Where do I find the fabled 15 minute enrichment timer so I can try disabling it?

I assume it should be on one of the water manifolds with just 2 wires running to it

 

It is on the A bank rear water manifold. It is to the rear of the outlet to the heater and has two wires to it. Just remove the wires and tape them off. If you have a USA spec car it does not have the 15 minute timer.

 

That would explain why I have not been able to find it