Gentlemen, when I read the codes I got "354 coil primary/secondary. The number 4 is on the side with the air intake. It was suggested to switch 4 with 3 and see if the code changes to "353". Because that's a lot of work, can I safely assume that it's the coil on #4?

 

yes or the plug or connector to coil, that's why if you swap coil it eliminates one of them.

 

If that's a lot of work I hope you have no other problems. Be advised that the location of #4 depends on whether you have a 4.0 or 4.2 engine.

 

It's a Jaguar - you can't 'safely assume' ANYTHING.

Graham