Thanks for reporting back and now we know the fuel rail pressure sensor appears to also be a fuel temperature sensor. Jaguar sure didn't label that very clearly anywhere!

My OEM plugs that I removed were NGK ILKAR7C10 in my 2014 60K Mile XJR. I replaced them with the same. No problems before or after. They come pre-gapped but I still check them. Only a few very minor adjustments were needed.
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Yes, that sensor is the pressure regulator and temp sensor. That was confirmed by the parts guy at the Jaguar dealership who actually seemed quite knowledgeable on these X351’s and gave me a couple other “hey, it’s good to know..” kind of things while there. He was the guy I called when hunting down the correct plugs.

I think the problem with parts replacement in these cars is figuring out what’s what. LOL.

My car seems to prefer Bosch and ONLY Bosch. It’s been an expensive and annoying lesson to learn.

 

Rock Auto had a short article on pressure/temp sensors in their monthly newsletter...
RockAuto December Newsletter | Early Edition

 

Good article but I wish Jaguar had just properly labeled the sensor in the first place?
Why they did not is a mystery and as you can see from this thread that it caused a lot of problems for SuperChargedXJR.

The code he got was right on but with no fuel temperature sensor listed anywhere that I can find how are we suppose to diagnose and fix the problem?
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