2000 XJ8 98K miles, I’m original owner but drive it infrequently since have other, newer cars.

For a couple years I smell fuel in the cabin, sometimes, when start it cold.

Last year I got CEL & my OBD-II pulled “P0442 evaporative emission system leak detected (small leak)”

I have not had the CEL come on for at least 6 months now.
However, that code was still stored in the computer, when I last checked again with my OBD-II reader a couple months ago.

I did some searches and found several very old threads and many pointed to the gas cap. Some suggested vacuum solenoid on the evap. cannister or tubing from gas tank to evap. Cannister.

I will be bringing it in, in the next couple of weeks to my Indy mechanic for this & other (unrelated) issues. (Steering column & door lock)

The gas cap looks fine to me but I recently read about people changing the gasket/seal on their gas caps so they didn't have to replace the entire gas cap. This was when they saw that their seal was cracked or broken.

I see a fairly wide flat seal on mine and it seems intact. I also read about lubricating it with engine oil so I dipped a finger into some Pennzoil synthetic oil and very lightly ran it around the seal.

I just did this today so it'll be a while before I know if there's any difference in the fuel smell in the cabin.

I can purchase a new OEM jaguar brand gas cap for $50-$60. There seem to be two part numbers that fit my 2000 XJ8 and I cannot find anything on what the difference is between the two.

NNG5942BB
&
NNG5942AG

I tried searching to see if I could find a new seal and maybe a YouTube video showing how to replace it since I don't think you just pull it out and push in the new one. I think I would need to disassemble the gas cap but… IDK.

If I knew the problem was the gas cap I'd have no problem spending $60 to simply replace it. But I don't know that. That's why I was looking to see if I could buy a replacement gasket/seal and try that.

1. Is a replacement seal available?
2. How do you replace it?
3. Would a bad gas cap seal explain a fuel smell in the cabin upon cold start …intermittently?


Thanks!