1984 Jaguar XJ6 4.2
 

i need some help car has a no start condition it has spark from the coil injectors has key on and cranking power but i am not getting the ground pulse from the computer and there is a white with blk stripe wire that goes from the negative side to coil the ecu and i am getting that signal to the ecm any help would be great and i also tried another computer from a parts car i have

Hopefully a mod will see this and move it to the Series III tech section

Easy check:

Are all the ground wires at the rear of the water rail intact? Clean connection? The entire fuel injection system grounds at this location

Cheers
DD

AJ6 Engineering has a 6 page study which is worth reading. No Start conditions are explained.

Fuel injection and the Jaguar XJ6 4.2 Series 3 / AJ6 Engineering

I'd also have a quick read of Doug's excellent "Cranks but won't start" checklist, here:
ENGINE CRANKS BUT WON’T START Series 3 XJ6
And since you have a parts car nearby, swap out the red pektron diode and the power resistor (DAC1211) on the RHS fender well...
I'm in NC too, near Salisbury...
Cheers
David
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