Jaguar Repair: 87 XJ6 injectors not firing, duration control, noid light

Question
My '87 XJ6 seems to not be firing the injectors. When I connect the noid light, I
get no flashes. I recently replaced the cold start injector, and the engine will fire
but die after 2-3 seconds. Classic symptom.Is there anything other than the ECU
that could be the issue? I there an easy way to see if the ECU needs replacement?

Answer
Hi Peter,
When you have no flash from a Noid light you first need to confirm power to the injector. Then confirm ignition and that the ignition signal is received at the ECU plug connector. You also need to confirm power to the ECU and the several grounds at the ECU and the "Start" signal is at the ECU.

The ECU needs all of these to be able to ground the injectors. All of the other signals to the ECU just change and control pulse duration (Control mixture)

If you don't have a good diagram of the wiring at the ECU let me know and I will put one up on my web site for you to copy.

It is very rare to see a bad ECU in a series III Jag.
Howard