This stuff is really good. I'm a huge skeptic of fuel additives or gizmos that claim to increase power or mileage. But this stuff does what it says it does: clean out your car's fuel system. I've had good results smoothing out rough running engines. Gas mileage sometimes increases, as much as about 10 percent.

Also, check your car's last emission test results. If it didn't pass by a healthy margin, use a can of 44K right before your next emission test. It'll go a long way toward giving you the best test results possible. But don't just use it to pass emissions. Ideally, you should use this about every 3,000 miles; this should reduce you vehicles emissions significantly all the time.

Generally, you can find BG products at some gas stations, as opposed to auto parts stores. Stations often have a BG sign in the window.