You know how the pump handle clicks off when your tank is full? I’ve had difficulty in the past getting the gas to pump, some pumps worse than others, but today, the pump handle was clicking off every other second while I was trying to fill my car’s fuel tank. This happened almost immediately after starting to fill the tank, so it can’t be that the tank had become full. Sometimes holding the lever in just halfway would get it to pump awhile longer, while pressing it 100% inward would cause it to click off. Why does it do this?
There is a small pipe in the nozzle connected to a venturi. Air from near the pump is sucked into this nozzle. When the tank is full, the air is cut off from this pipe, and the pressure changes, causing the nozzle cutoff.
Sometime, however, just the turbulence of the fuel pumping can trigger the pressure cutoff. It can also be caused by splashing in the pipe to the tank, or airflow out as the tank fills. Sometimes the nozzle pressure switch is faulty. My solution is to fully remove and reinsert the nozzle, fiddle the angle and rotation, withdraw the nozzle an inch or so, or just not hold the flow control handle fully on.
Si
If we are talking about a fairly new car if there are issues with the car itself, the pump can also click off right away. If the evap system in the car is plugged, the fumes may not vent properly and the tank becomes very hard to fill.
Don’t let the pump nozzle rest on its own weight, lift it a little so the nozzle tip is parallel relative to the car’s fill hose. Also it helps if you don’t insert the nozzle all the way in, pull it a little back.
The Toyotas made in the last 4-5 years are notorious for being hard to fill. If you rest the fill nozzle on its own it gets in a really weird angle and that causes turbulence and shuts off the gas pump nozzle.
To add to Ricks post,
Ford pickups '03-05 >< with the restrictive fume evap. systems and off road as in mud and dirt. Our vehicle maintenance department stared putting an external disposable fuel filter on the breather line from the evap canisters and changed out a $3.00 filter instead of a $200. emissions canister.
I was shocked to see how narrow the fuel fill hose is on these evap systems.