1991 XJ40 4.0....

Replacing an injector. Is there any special knack needed removing the injector from the special tools, sensitive areas, etc)?

 

If memory serves, you just remove the clip and they release?

(Wait for confirmation on this though!)

Larry

 

Yes that tin clip has to come off. Mine were quite stiff and I had to pull hard, but it's just an o ring in there. ( I ended up using a flathead valve spring compressor to pull a couple out of the head)

 

I just did this on mine a month or so ago. Unhook your battery cable (don't need any sparks with your fuel system open) and relieve the pressure from the lines. Unhook the rail on each end and unplug the pigtails from each injector. If I remember right there are four bolts holding the rail to the intake manifold. Once you remove those, you should be able to pull the rail and injectors out of the intake. The injector retainer clips come off easily, I used a screwdriver. After that, the injectors take a bit of force to remove (grab and twist while pulling away from the rail), but they aren't bad. Just make sure you replace your o-rings... I had a fire in my BMW e30 because i pinched the fuel pressure regulator o-ring when I installed it.

One thing to keep in mind, the plastic plugs for the injectors can get brittle and break really easily. You can buy new ones but you'll have to splice them in to the harness.

 

Ok that worked... Injectors installed in rail quite easily...

However, the rail is not aligning with the fuel regulator. The rail I have is from a 93-94 XJ40, mine is a 1991. The salvage yard that sent it to me swears that the rails are the same from 1990-94.

I called the largest Jag dealer in Southern California... this guy who's worked on both models assured me that the rail for the 90-92's are indeed different from the 93-94's. I'm totally confused and frustrated.

All I know is the this 93-94 rail is not aligning properly. Is there anyone out there that actually knows about this?

 

I can't be sure, but according to SNG Barratt's website, the 3.2, 3.6, and 4.0 all use the same rail, and the 2.9 uses a different rail. Maybe they sent you the 2.9l rail by mistake? The link below is a breakdown of the 2.9l system, is that what the rail you just put on looks like?

https://www.sngbarratt.com/us/#!/Eng...IL-2.9%20LITRE

Checking JagBits, they list a fuel rail for a 1993-1994 XJ6, so it seems like they list it as being different...

 

There are AFAIK two versions of the fuel rail used on the six cylinder engine - EAC9690 for the 3.6 litre cars and EBC3679 for the 3.2 and 4.0 litres. They are slightly different but are interchangeable - and Jaguar list the later one as a supersession part for the earlier type. A 1993/94 should fit your 1991.
My own car is a 1993MY and I have fitted a 1987MY fuel rail to it.

Is the new fuel rail slightly bent perhaps?

Edited to add link:

https://www.jaguarclassicparts.com/u...-3-2-4-0-litre

https://www.jaguarclassicparts.com/u...tors-4-0-litre