Thanks for the replies.

James:
- I'm 99% certain it is the original wiring harness
- I have not read the codes yet. I'm mostly a diesel guy and at the moment I'm confused over which code reader to buy. Suggestions?

Harry: What pressure should I get at the fuel rail? Is there a standard test procedure for this? Could the fuel delivery cause problems with idle but still be fine at WOT? The car goes like stink!!