Why does the gas nozzle keep shutting off while putting gas in an 89 Ford F150?
The gas tank vent system is plugged up. It could be the hose or the charcoal canister. This diagram might help ---
The pump is shutting off because it detects back pressure, as if the tank is full. Back the nozzle out just a little and try filling at a slower rate. Also, visually check the condition of the fuel tank. I've seen newer newer F-150 collapse the fuel tank when the purge valve becomes defective and implodes the tank during vacuum testing.
I agree with both experts but lean more towards first answer. In the meantime manually pull the nozzle safety back and see if gas goes in, if it does, u have an issue with vent system, it it still doesn't then u have a restriction in the fuel tank hose
I have seen this happen on a car that someone tried ti siphon affelsgas and bent the baffles the hindered the flow on filling.
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