Hey all! Have been messing around with my 1992 XJS V12 HE Marelli, and have run into a few issues. First, I'm going to list what I've done to the car ( engine wise) to get you all up to speed. - All coolant hoses/ Rad caps/ thermostat
-2 of the coolant temp sensors ( "A" side)
- Valve cover gaskets
- Intake manifold Gaskets
-Smog Delete as per https://foreverjaguar.com/f/smog-blogdelete Total delete
- Many vacuum/fuel hoses
- Injector o-rings
- Spark plugs
- Fuel pump and filters
- Both ignition coils
- Both Air filters
- Fixed crack in AAV hose with many layers of bead sealer
-Completely cleaned gas tank and replaced old gas with fresh 100% 91 octane.

The PO gave some receipts for having a dizzy cap, rotor and wires replaced a couple years ago. I have not checked to see the condition of them.

The issue I am having is that the XJS feels like it has no power. It also likes to die when put in gear. It will idle all day long, starts on the first crank, hot or cold. Idle is about 8-900. Idle in gear drops to 6-700. I can rev all the way to 5000 RPM in Park or Neutral, but in drive/reverse, I can only get about 1200 RPM. Also, the coolant gauge does not work. This is why I replaced the two passenger "A" bank sensors. I also have a CEL, FF13. From my reading, this is a generic code that has no definitive meaning other than something is causing some misfires. Any help would be appreciated. Thanks

 

On a Marelli car with low power you gotta check the rotor just on general principles. I wouldn't do anything else until then.

Cheers
DD