In my experience you have the most difficult car to diagnose made. Having said that would you consider yourself car savy? electronic knowledge? have a DVOM? Did problem occure after cleaning injectors? Try this key position II on DO NOT start press VCM on VCM/trip display. check engine light will flash so flash pause flash,flash= 12

Answered by Docfixit (expert)
18,416 answers provided

Unfortunately the 88 XJS does not have a check engine light or a VCM button on the trip computer (see attached). I am pretty car savy and I do have a DVOM.

The car had been sitting for several years so that's why I had the injectors cleaned. I also had the gas tanks cleaned, flushed all the fuel lines and installed a new pump and filter. Prior to this problem I started the car about 10 times and let it run for several minutes with no issues.

Response from 88kitty
1 question asked

Your right V12 no diagnostics so basic testing is needed. Exhaust backpressure, fuel pressure, crank sensor ect. My experience on Jag's in the 80's is that attempting to clean injectors results in there failure and replacement needed I found out hard way and had to eat injector for customer. You will need a manual for testing

Answered by Docfixit (expert)
18,416 answers provided