See if you can get one of these, (or a pdf equivalent).It's a Mine of Information.

https://www.ebay.co.uk/i/233102720786?chn=ps

Also have a read here:-

Fuel injection and the Jaguar XJ6 4.2 Series 3 / AJ6 Engineering

It takes you through the whole EFI system and what can go wrong. Unlike systems of today, the Lucas/Bosch L-Jetronic EFI system is analoge, so forget about digital and fuelling maps, they don't exist here !
The fuel pump is kept running via the fuel pump relay and this is supplied with volts, (except at starting), via two small contacts in the mass flow meter. Over the years these lose their springiness and can fail to make contact, so the car starts and when the ignition switch is returned from the "Start" position, the supply ceases and the engine stops. Other thing is to clear out the fuel tanks and clean the filter gauzes, plus replace the main fuel filter in the engine compartment.

The whole EFI system relies on pulses taken off the back of the coil. Without these the EFI will not fire the fuel injectors. As others have said, the Cold Start Injector eases a cold start, but is not totally essential you just have to crank the engine more.

 

USA owners will want this:

Fuse Conversion Chart


Cheers
DD

 

Wow, who knew (except Doug and Kirby Palm)? I am definitely going to print that out and tape it to the page in the manual where it lists the fuses. I always thought they used mighty big fuses for the circuits they were protecting. Thanks for this valuable information.

Jeff

 

I agree! That chart is an eye opener. Who would have thought.