I have owned my XJ-S for 6 months after purchasing from the family of the original owner who has maintained meticulous servicing records since new. Quite incredulous one might say for a 32 year old vehicle. One thing that does not appear in the log book is servicing of the injectors. This may well have been undertaken, or am to assume that the injectors are not withdrawn to check flow until engine performance determines that they should be looked at. This is my first experience of an injector petrol motor and therefore would appreciate any advice in the maintenance of injectors if any. Mileage 80k

many thanks.

Mike NZ
1986 XJ-S 3.6 L 5 speed manual.

 

They can be serviced/cleaned "off car" or "on car".

The on car method typically involved some sort of flushing machine attached to the fuel rail so that a powerful cleaner can be introduced into the fuel while the engine is running. Generally this type of service works well.

Off car cleaning means removing the injectors, obviously, and is most commonly done only when the injectors are off for another reason or if there's reason to think there is an actual fault with them (as opposed to merely being a bit degraded and dirty commensurate with age and mileage). A good injector shop will check flow rates, spray patterns, check for leaks, install new screens, etc.

Every car I've owned, jaguars and others, has benefited from injector cleaning of wither type

Cheers
DD

 

Thank you Doug. I must admit the car runs extremely well, great acceleration, maybe I should let’s things lie. The old adage “if not broke don’t fix it” applies.

 

In my experience it was worth it to send off injectors to get rebuilt, as per the tests the flow rates were restored to or exceded spec, gaining as much as 20% over their previous condition.

The earwax that builds up can't be pushed through the little basket filter, another choke point is the swirl tanks on V12s, not sure if yours has the tank and sock filter.