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Mazda3 - filling gas tank question

We have a 2005 Mazda3 that has a ‘hitch’ when filling the gas tank. We can only fill the tank a cup at a time - the gas nozzle clicks off frequently and it takes FOREVER to fill the tank. I’m guessing there is a faulty ‘valve’ of some sort. Is this a major or costly problem to fix? I think I heard Tom and Ray talk about this once, but I don’t remember the verdict, but I do remember the laugh!

The problem is most likely with the Onboard Refueling Vapor Recovery system.

This system is designed so that as the gas tank is being filled, the gas tank must first vent thru the carbon canister prior to being vented into the atmosphere. If there’s a restriction in this system it cause difficulty when filling the gas tank.

I don’t know what you heard that made you laugh but, there have been reports that spiders can build nests in these systems, causing this exact same problem.

Tester

There are a number of possibilities but they all come down to the same thing. If you are the mechanical type, you need to have it checked and corrected by someone who is.

Modern cars have anti-pollution vapor recovery systems. Those systems as well as safety devices that help prevent fuel spills in the event of an accident can cause this problem.

If you are in the habit of topping off the tank after it clicks off (before you noticed this problem) you may have caused it. If you car has a warning label in the glove box or on the fuel cover telling you not to top off the tank, that may well be it.

Repairs are likely to run a few hundred dollars.

Thanks, we’ll get it checked out. My son bought the car used last fall and he doesn’t ‘top off’. (Never has more than $10 for gas at one time!)

What’s your cost estimate?

If there isn’t a check engine light on, it couldn’t hurt to push a flexible rod down the gas tank filler tube and push against the check valve at the bottom of the tube. This won’t necessarily help, either. It’s just a “maybe”.