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Curiosity question: stalling after filling up with gas

General Discussion
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#1

I have a question out of pure curiosity. Last month we were on a trip and stopped somewhere in NJ to get gas. The gas nozzle had what I’d call a fume catcher or sleeve. Immediately when I tried to start it, it stalled out. Then it started immediately.

I know this is due to the filter getting overwhelmed and causing the computer to overreact. (we had a 2005 Caravan which was notorious for doing that.)

Now my question is, do people who live in states that require these fume catchers or sleeves experience this at a higher rate than those states who do not?

#2

Hee in NH and MA, some stations have them, some don’t. Never heard of them causing problems.

Ran across this article from 2012:
EPA to remove vapor-capturing rubber boot from gas pump handles
The Obama administration and the Environmental Protection Agency announced Thursday they intend to phase out the rubber boots on gas pump handles now used to capture harmful gasoline vapors while refueling cars.
The EPA says the vapor-capturing fuel pumps are redundant because more than 70% of all cars on the road today are equipped with on-board systems that capture the harmful vapors.

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#3

In the Bay Area of Northern California we have those boots everywhere. They don’t cause the problem you describe. You were in New Jersey where they still insist on gas station attendants, no self service. The attendant probably tried to “top off” the tank.

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#4

Good point. The few gas station attendants still around seem to insist on topping off. The last time I got gas with an attendant, I stood next to him and said “do not top off” repeatedly, but he still did.

#5

Thanks! But interestingly it was self-service. NJ may have recently changed. The manager did come out to talk to me which I thought was a little interesting.

This is the only time it’s every happened.

#6

Everywhere I’ve lived have had those rubber boots on the nozzles. I’ve never experienced a stall after a fill up though. Stalling after a fill-up can be caused by a leaky purge valve. The purge valve is what opens and allows the fuel vapors stored in the canister to be burned in the engine. It is only supposed to open at certain times. For example when you are driving down the freeway at 60 mph it’ll be open. It should be closed when refueling and when idling, but if it leaks it will allow gasoline fumes from the canister into the intake manifold, and flood the engine with a too rich mixture.

It’s true that the boots don’t accomplish anything on newer cars. On older cars – roughly older than 1995 models – the boot blocks off a small vent hole adjacent to the hole the tip of the nozzle goes into. If that vent hole didn’t get blocked off, as you filled the tank the incoming gasoline would push fumes out that hole and into the atmosphere. Blocking off that hole with the rubber boot forces the fumes from the tank to go into the canister during re-fueling. Models post 1995 have sensors that somehow know when refueling is taking place and by opening and close a bevy of valves do the same job as the boot does.