Don’t overfill gas tank

Q: My 2014 Prius needed a fill-up, so I stopped at a station that had a slow, low-pressure pump. After it filled the tank, it did not automatically shut off. I recognized the problem and shut it off before gas spilled on the ground. But I did end up overfilling the tank. Does this cause any harm to the fuel system?

A: If liquid gasoline enters the evaporative emissions canister, the canister might have to be replaced. If the check engine light isn’t glowing, you’re probably OK. Stop filling when the nozzle clicks off. If you wonder why, read on.

Q: Since I overfilled my tank, I have a refilling problem. Being a parts replacer (limited diagnostic skill), I replaced the EVAP components (EVAP solenoid, charcoal canister and purge valve). None solved the problem. I recently removed the tank hose vent that connects to the charcoal filter, and with the gas cap off, could not blow in either direction. I should be able to, correct? My next step is to drop the tank, but I would like your advice first.

A: I’m afraid that might be inevitable.

Q: I am thinking about buying a plug-in hybrid, which, given my current driving, will likely use the gas engine less than 10% of the time. I know that even so, I will need to have the oil changed at least annually, but what about the gas in the gas tank? A tank of gas could last me a long time, possibly a year or more. What do I do about that?

A: Gasoline in your tank can last about six months or so — longer if you add some fresh gas to the old stuff in the tank. If you mix in a fuel stabilizer such as STA-BIL, it may last from one to three years.

Bob Weber is a writer, mechanic and ASE-certified Master Automobile Technician. His writing has appeared in automotive trade publications, Consumer Guide and Consumers Digest. Send automotive questions along with name and town to motormouth.tribune@gmail.com.