what makes the gas pump nozzle keep shutting off when filling my tank on my 2007 gxp
2007 Pontiac Grand Prix GXP with trouble code 446, and hard to fill tank without the pump nozzle from shutting off repeatedly.
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.
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