Hi all. New here.
need help/advice.
I have 1990 XJR 4.0 6 cylinder.
Cranks But wont start.
I have spark.
I've tried to clean injectors by removing and spraying carb cleaner though while pulsing (by hand) 12v. They are not blocked and appear to be working (although to my untrained eye, they don't seem to be atomising the fuel as much as I would expect).
I have good fuel pressure to the rail.
The CPS was faulty (fuse 1 fail error) replaced the CPS and that error has disappeared.
Still no start.

Next steps (I was thinking) is to check compression, maybe bore wash???
Im a bit stumped and don't want to spend money unnecessarily.

PLEASE HELP!

 

Sorry, title is supposed to be "Engine CRANKS but won't start.

 

1990 or 94.5 to 97 as the round bodied X300 ? Yours may be the earlier square X40 version with a slightly different inline 6 SC

 

Yes, I think you're correct. Sorry, new to all this Jaguar stuff.

 

The X40 and the supercharged 4 door same X40 chassis version as the XJ81 has their section that has a different chassis electrical design as the later X300 replacement was a whole new design and test points

 

So, the crank sensor was bad. I changed that and now no errors and I have spark. I have compression and the injectors are firing (possibly not very well)

 

The injectors were definitely bad. Bench tested the new ones and they spray 100% better than the old ones.
Then discovered that there wasnt constant fuel pressure. It appears that the check valve in the online fuel pump had given up. Replaced the fuel pump and she runs!!!!

 

 

What was your injector bench test method ?