Strangely, if I fill up at Shell or Valero, gassing up is normal. But if I go to a Mobil station, the pump shuts off every few seconds, making it impossible to add gas. Anybody else had this issue?

 

I had that in my old Ford Pickup. Turns out the Evap Canister was a bit clogged from dust and dirt, and the tank over-pressured and shut off the pump flow. It didn't happen at every station, just the ones that tended to pump fuel faster than other stations.
After I changed out the canister, everything was wonderful.

 

It happens to me at USA gas stations but not Shell or Mobil or Valero. It's the sensitivity of the nozzles to the back pressure that causes this. Sometimes by turning the nozzle upside down, I can get it to work better at pumps that are giving me problems.

 

Yes, on 2/9 fill-ups so far. This has happened on two distinct fuel stations, on both of which I've also filled up without issues. Rotating the nozzle didn't help, filling up veeery slowly did. Still annoying.

Does the XK have a similar setup?

 

I think there are a few things going on here. I use Mobile all the time and I have one station with one pump that I have that problem with. If you look at the filler hose from under the car you can see the evap unit is located on the left side near the top of the fill hose. If you insert the pump nozzle all the way in it will cover the evap hole. Also the filler neck is pretty small and it has a rubber hose that goes to the tank. So if you are filling full throttle you get some pressure feedback which will trigger the nozzle if it is set to sensitive. Also because of a sealed system the only place air from the tank vents is through the fill hole during filling. Just some observations.

 

Yes. Ans I'm in SO FL also, but only at Chevron, and only at certain pumps. The dealer couldn't replicate the problem, but thought it may be a pressure variation issue from pump to pump and for some reason the car is overly sensitive to such variations. I think it was a real issue with the XF and there was a TSB issued, but not for the XK.

 

Yep, only the tip needs to be in.

Xk has a small long fill pipe. Volume that goes in the tank need to vent back out. I don't force the nozzle all the way in and only pump on the first notch. Takes longer to check the oil and coolant than to fill the tank.