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Toyota Prius on a hunger strike

I have a 2008 Prius. When I try to fill it up, it bucks back against the nozzle. I can get gas in in little drives and drabs and the gas gauge doesn’t show that new gas has been added. I tried three different stations before I took it to the dealer. The mechanic took it to a fourth gas station himself and had the same experience. He says it will require a complete tear down just to see what’s is wrong. Oh dear. Sounds expensive. Any advice? Judy

My guess is the evaporative controll system is plugged up somehow. When you fill up, do you always stop at the first click, or do you ‘top off’ the tank? Topping off forces gasoline into the evap system, and can damage it.

Many cars have a flapper valve in the filler neck to prevent gas from pouring out in a rollover accident.
If “a complete tear down” involves dropping the gas tank and inspecting the filler neck it shouldn’t be too terribly expensive.
This kind of work doesn’t require the dealer if it’s not warranty.
An independent mechanic might be a better deal.
Shop around.

Attached is a sketch of a typical modern emissions system.
http://tijil.org/Scion_Docs/Scion_06_misc_docs/2007sciontc_ncf%20Folder/2azfeemi.pdf
As you refuel, the air in your tank should be released through the in-tank valve (which is that “spill valve”), through the refueling valve, through the charcoal canister, through the air filter, and out the fresh air line.

If either of these valves is stuck or the charcoal bed saturated, the air will not be able to escape to allow the gas to enter and you’ll experience your symptoms.

On most vehicles these things are all in assemblies dropped into the tank and/or under the chassis.

Check over on the Priuschat forums.

The Prius does not use a “normal” gas tank but I believe it has some sort of internal bladder system in it.

I did a quick google search for “can’t fill gas tank on Toyota Prius” and came up with a number of hits that appear to deal with this.