My wife's 2007 XK (147K) has a recurring P0193 code. My mechanic has already replaced the fuel rail pressure sensor, but the code is back. I saw posts indicating that pressure should be constant 55 psi. I was measuring 58 psi via OBDII while idling; I didn't check yet while driving. I did notice that, when I turned off the engine, the fuel pressure went up to 78 psi.

On other forums (X-Type, X100), I saw recommendations to change the fuel filter. That surprised me, as I presumed a blocked filter would cause low fuel pressure, not high.

Any thoughts on what could be going on here? I guess another faulty sensor could be the culprit, but I'm wondering if something else in in play.

Thx,
Doug

 

I'm looking into this also. I replaced my sensor due to a fuel leak (among other repairs I was doing at the time). Then the code started showing up. Someone was saying they replaced the fuel temp sensor and it went away but I find that hard to believe.