Hello: My 1990 XJ6 Soverign has one cylinder which is not firing. I have ruled out the spark plug, the spark plug wire (it's sparking with a new plug and I switched the wire with another wire), the injector and compression. I assume this leaves the injector electrical connector, the wire to the injector, and whatever controllers are before that which make the injector work. Any suggestions?

Lanny

 

If you ruled out the injector, then the harness should be OK. Injectors would not work if there was a problem with the harness.

How did you test that the the injector good, if you think the harness or a controller is bad?

Just trying to figure out your diagnosis path.

 

There should be an audible click as each injector fires. You can check using the ear-against-a-screwdriver trick.

 

But he wrote this...


confused as to HOW he checked the injector in the cylinder that "is not firing".
Ohm'ed..switch injectors, etc?

 

I switched the injecter to another cylinder.

 

I think you'd get more info in the XJ40 section.