Hi all, Can anyone tell me how the fuel pressure test is to be done on the late V12's with the later generation of fuel rail ? Does it need an adapter in the feed line to the rail ?
Mine is an LHD from 1992 chassis number P186445 Any help greatly appreciated. Steve.

 

I have a ‘92. I cut the pump side hose and put in a T. Hose was from 1992 and was due to be replaced anyway. FYI for 1992 only, the fuel pressure is 2.5 bar not 3 bar like all later 6.0 cars using that same style fuel rail.

 

The fuel pressure regulator will have 2 fuel lines with one to the fuel pump and one a dump back to fuel tank ( low pressure )

You want the hose from the fuel pump even though the fuel pump pressure capacity is higher than FPR setting ( you are reading FPR setting as injector pressure ) the over pressure is bleed off by the regulator and goes back to tank

Your fuel pressure may be in this Doc in the V - 12 section

This V- 12 section is in 2 parts : the early V - 12 and later V - 12 ( ND ) denoted by the engine ECU (. the ' M " one vs, the later Nippon Denso ( ND ))

801S TITLE

 

I read this thread and saw 1992 and forgot which forum I was on. This forum is for the 1995-1996/7 XJ12 sedan. What kind of Jaguar you got there? 1992 would be either an XJS or a Series III XJ12… but the Series III XJ12 never got the later style fuel rails so I’m confused a little.

 

Thank you, but that does not tell me if I have to cut pipes, fit a tee piece and cap it off afterwards, or if there is a pipe available to do the job. It is an XJS by the way.

 

Might find more information for the XJS chassis / engine / fuel lines in this section , to start a new thread or maybe search

XJS ( X27 ) - Jaguar Forums - Jaguar Enthusiasts Forum

 

Hi, sorry, mine is an XJS V12 I should have made that clear.