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Filling the tank

I recently filled my tank to the max where I could see the gas at the brim - after all, I hadn’t seen gas that cheap for years - $1.72 a gal. When getting back on the highway, driving 60-65, the car hesitated at times, slight, but you could feel it. After using about 3/4 of a gal, based on how many miles I went, I stopped, unscrewed the gas tank cap, waited a minute, put it back on, and resumed my trip. It hesitated once more, but as I continued on, it didn’t happen again. Does filling your tank to the max cause these kind of problems because of a lack of air in the tank?

That, or you forced liquid gas into the vapor recovery system. Don’t do it!

It’s not lack of air in the tank that’s the problem.

Filling the tank to the brim causes liquid gasoline, as opposed to gasoline vapors, to be drawn into the car’s evaporative emissions control system, which is not designed to handle liquid. Many cars need expensive repairs when this happens.

I’m sure your owner’s manual cautions against overfilling the tank.

Has the check engine light come on?

If I were you I’d pray that once is not enough to do significant damage, and learn to stop filling when the pump clicks off on its own.

That is exactly why you are not supposed to top off your tank. As soon as the pump automatically clicks off you should be done. Say a prayer and don’t do it again. You might be lucky not to have damaged anything.

No engine light came on and the car has been operating fine since, after driving 300 additional miles. I’m praying that any damage done would have showed up by now. Are my prayers likely to be answered?

No engine light came on and the car has been operating fine since, after driving 300 additional miles. I’m praying that any damage done would have showed up by now. Are my prayers likely to be answered?

Hard to say. Take two more tankfuls on the first click, and call me it two weeks.