A Redditor who goes by Okgal2112 took her car in for an oil change when she was 21, but what the mechanic said has stayed with her since.

He, “came to my window and told me that I needed to clean out my gas tank before winter hit.” It was a maintenance procedure she’d never heard of. His reasoning. “That way my car ran correctly. He said that I didn’t /have/ to do it, but that it would help.”

She asked for specifics. He said gasoline  “can stick to the sides of the tank, so it’s good to go in there and clean it every once in a while.”

When she protested, the mechanic insisted he wasn’t pushing a hard sell. “He said that he could do it right then for me, or that I could come back a different time.”

The young woman didn’t buy it. “To be frank, that sounded like bullshit to me so I said that I would come back.”

Driver asks internet for advice on scamming mechanic

The driver immediately decided to phone a friend. “Called my dad who said that he wouldn’t be surprised if that was a thing, but he didn’t think it was.”

They agreed to not worry about the pre-winter gas tank clean out that season. But the driver wondered about it from time to time. So she asked Reddit: “Is this a thing that people do, or was this mechanic trying to scam me?”

The consensus was loud and clear: Scam!

But there was a bit of nuance to the response. One commenter said a gas tank cleaning is “usually done as a step for restoration project.” What they mean is a classic car, abandoned for decades, may have a rusty tank filled with a mix of bad fuel and water. A specialist may drain it, fix the rust, or even coat the inside of the tank in a liner so none of the rust gets into the fuel system.

A second commenter made a very good point. “Many oil change places offer a fuel system clean. They hook up some contraption to the intake and it’s supposed to clean injectors and other parts of the engine, but not the tank. I wonder if the tech explained it wrong.” But there’s a reason this procedure isn’t part of any dealership’s standard service: It’s likely completely unnecessary. You can read the original post, embedded below:

Is cleaning out your gas tank a real thing?
byu/Okgal2112 inAutos