Did I damage the engine by flooring the gas pedal when I started the car?

Dear Car Talk

Dear Car Talk | May 01, 2001

Dear Tom and Ray:

As a 15-year-old (soon to be 16), I'm getting a little excited about driving, as is a friend of mine. Anyway, my mom has a 1978 T-Top Special Pace-Car Edition Corvette that just sits in our garage. It's a beautiful car, two-toned black and silver. Well, my friend and I were getting kind of bored, so we went out to the garage. He immediately saw the car, so we got in and sat in the silver leather bucket seats. He was in the driver's seat. He was curious to know how it sounded, so I gave him permission to start it up. He turned the key, but it wouldn't start. So I explained to him that with older cars, like this one, you had to "give it some gas," as my grandfather had told me. Well, I guess he has a bit of a "lead foot," because in the process of "giving it some gas," he floored the pedal. After that, the engine immediately roared to life. It sounded beautiful to me, and the large engine made the fiberglass body vibrate. But after the car started, a big cloud of smoke was immediately blown out of the exhaust pipe. It disappeared after a second or two. But my question is, was the car hurt by flooring the pedal like that before starting it? And what was the reason for the smoke? -- Craig

RAY: That's it?? We thought you were going to have an exciting story about breaking through the garage wall or something. But that's all you want to know? Well, that's easy.

TOM: Pumping the pedal before starting the car wouldn't do any damage to it, Craig. Keeping it floored right AFTER it starts is another matter (one that could cause serious engine damage). But flooring it before starting the car just dumped some excess gasoline into the cylinders.

RAY: And the smoke was one of two things: If it was black-colored smoke, it was just the excess gasoline exiting the car after being partially burned. And if the smoke had a blue tinge to it, it was probably just some motor oil that had gotten into the combustion chamber while the car was in storage. Either way, your friend didn't do any damage.

TOM: For future reference, on an older, carbureted car, the correct procedure for cold-engine starting is to step all the way down on the pedal once or twice, then take your foot off the pedal and start the car. Depressing the pedal like that sets the choke and deploys the accelerator pump, and that should allow the car to start and fast idle until it's warmed up.

RAY: For more modern, fuel-injected cars, you shouldn't have to do anything with the pedal. Everything is controlled by the computerized engine-management system, so just turn the key and leave the pedal alone.

TOM: But before you go and try this again, Craig, go rent "Ferris Bueller's Day Off" and "Risky Business." Those movies will give you a few good ideas about "activities to avoid."

Get the Car Talk Newsletter

Got a question about your car?

Ask Someone Who Owns One