Dear Car Talk:
I own a 2013 Chevy Sonic with a turbo engine. I love the car and it gets great gas mileage. I don't drive like a grandma, but I tend to drive a little on the easy side in order to maximize my gas mileage. I get in the upper 30s to lower 40s mpg.
My buddy, who is a mechanic, says that I drive my car too gently. He says driving the way I do does not let the engine get hot enough, and I need to periodically "put the pedal to the metal" in order to "blow out the carbon."
He says this is especially true with a turbo engine, as you need to "make the turbo howl" every once in a while. I know that taking too many short trips can cause problems with the engine not getting hot enough, but most of my trips are in the 15- to 20-mile range.
My buddy specializes in hot rod cars from the 1970s and '80s, so I think that is affecting his thinking about today's cars. Is my buddy right? Or are things different now? -- Ed
Your buddy has his headlight firmly implanted in his taillight socket, Ed. Put your fingers in your ears the next time he starts talking to you.
There is no carbon in engines anymore. Computer controlled engines, like yours, run so efficiently that they really leave no deposits at all to "blow out."
The goal of modern engine management is to protect the catalytic converter, minimize emissions and maximize fuel economy. To do that, the engine must burn the fuel as completely as possible, which leaves nothing behind. We almost never see carbon deposits in engines anymore. If we did, they couldn't be "blown out" by driving hard anyway.
As for the turbo, "turbo howl" is something that costs about $1,500 to $2,000 to fix in our shop. That's nonsense, too. The more gently you drive, the longer your engine and turbo will last. Period.
So yes, I think your buddy is still living in the 1960s and '70s. And I think he may have been exposed to too much leaded gasoline and exhaust fumes over the years. Set him straight about modern engines the next time you see him, Ed, and keep doing exactly what you're doing.