My 2004 XJ 8 left me by the side of the freeway a few weeks ago. I had it towed to a British Car place close by. They checked the fuel pressure which was 3psi. He said it had three codes They diagnosed it as a fuel pump, module or a relay, but no definitive fix. The codes were P1338,P0230 and P1235. He cleared the codes did a hard reset, un plugged the fuel pump and plugged it back in and everything worked fine. He kept the car for a few days and drove it around. No problems.

I took it home about a 30 mile drive then made an appointment with a more experienced Jaguar only place and drove it again about another 30 miles. They ran it thorough more diagnosis found one more stored code B2879. They too couldn't get it to act up again and had it for two days and drove it another 60 plus miles. They narrowed it down to a module software update, fuel pump or module.. I went with the software update since it was the least expensive.

Any ideas on what to do if it acts up again, Module or Fuel Pump? & what are the chances it needed only the software update or a connection?

 

found this, it's the only thing I have found with b2879, "Engine stops with fuel still indicated in the fuel tank. Instrument cluster DTC B2879"
http://www.jagrepair.com/images/TSB/...g%20Issues.pdf

 

Sounds like maybe a blockage in one of the small 2mm holes in the fuel pump? Maybe him moving it around and unplugging it cleared it or maybe it did so on it's own.

I wonder if running some fuel stabilizer or treatment through it would be beneficial.

We have terrible gas here in CA.