Can I disable half of the cylinders to obtain more mpg?

If I have a V-6 or V-8, can I disable half of the cylinders to obtain more mpg? I do not care about loss of horsepower to be honest most people don't, the bottom line is more mpg.

Jay, Louisville

This would not be a great “do-it-yourself” project for the average backyard mechanic. There are many variables to a successful cylinder deactivation system, and you simply can’t disable half of your cylinders to save fuel.

Automakers such as Chrysler, General Motors and Honda offer cylinder deactivation systems. GM’s active fuel management uses a two-stage valve lifter that closes intake and exhaust valves to de-active cylinders.

Not only that, but factory engineered systems are computer-controlled and look at multiple engine variables and sensors to choose the right situation to shut down cylinders. Automatic changes by an electronic throttle also make the system as seamless as possible to the driver.

Models that offer a cylinder deactivation feature include the following cars, SUVs and trucks:

Learn more

Answered by Joe Bruzek on June 11, 2008 in How Does That Work? , What Does This Mean? | Permalink

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