Over time and miles, your car might start to slow down. It might not accelerate as quickly as it once did; the engine may not run as smoothly as you remember, or the fuel economy may dip—but ...

Walk into any parts store and you'll see the rows of glossy bottles promising to stop engine wear, boost fuel economy, and make your old clunker run like it just rolled out of the factory. The auto ...

Over time and miles, your car might start to slow down. It might not accelerate as quickly as it once did; the engine may not ...