what makes the gas pump nozzle keep shutting off when filling my tank on my 2007 gxp

Sounds like you have a plugged vent hose or a plugged EVAP charcoal canister. You can try removing the hoses and blowing compressed air through it to clear it. I believe the charcoal canister is located behind the rear wheel on the driver's side, but I could be wrong.

On my older Pontiac, I had this very problem and the culprit was as follows: attached to the filler neck and between the tank there was a large diameter hose connection. It had become old and brittle and had collapsed to a small portion of its original opening size. I changed the hose, now no problems. I hope this helps you out.

I have a 2002 Grand Prix GT , with the same problem except the canister is cleared along with the vent hose , cleared ......... tried compressed air threw the neck to see if it’s cleared and spits fuel out the puke line ( rubber hose ) so that’s cleared but when I go to add fuel it acts like it’s full and spits fuel back out the neck help help help I’ve been searching a lot but have found nothing what so ever , even checked the fuel module along with using compressed air in the lines ...... any ideas