I have a 2010 xf supercharged 5.0 that for about the last month or so has just been running awful, it misses and cuts out at cold start. It starts and idles fine but as soon as you put the throttle to it to pull off it starts carrying on, cutting out and jerking terribly. When the car warms up some the symptoms lessen, and if I drive it 30 minutes or so, park it and switch it off, let it sit for 30 minutes, restart it will drive with hardly a miss, no codes whatsoever to this point weird? Took the car to the dealer, they said it was the mass air flow sensors, $800.00 later got the car back drove it for a day still acting up. Later that evening it threw a p0193 code, fuel pressure sensor high input. Back to the dealer. Tech says he doesn't think it is the sensor though. Showing low fuel pressure on the fuel rail but not sure if it is the high pressure fuel pumps or the ecm. Fuel pump in the tank checks out. Cleared the code advised me to drive it until it breaks as he is not sure what the problem is, so I am, so far it hasn't broke all the way or thrown any codes, but continues to be miserable to drive most of the time. I hope there is someone who has knowledge of what might be going on. Thank you in advance for any assistance offered.

 

I would look at the low pressure fuel (supply side) first. Low pressure there will cause low pressure at the High pressure pumps.

 

Hey thanks for the reply. The low pressure side would be the fuel pump in the tank wouldn't it? The jag tech said that one was okay as it was holding a continuous 70 psi. Any other thoughts you may have I would like to hear, I really want to get this worked out. It seems to act up less at high rpm or maybe just less noticeable. Maybe the higher rpm brings the pressure up as the high pressure pumps are cam driven

 

Darell I've moved your post to it's own thread for a better response.