Just like you get less attractive, cars lose horsepower as they age. It's simple math. But what if you could get some of that power back? You may think you need to do some serious repairs for that sort of promise, but as it happens, simple things like changing your oil, filter, or your intake filter can greatly boost your horsepower. The best thing you can do turns out to be cleaning out your fuel system. Do that, and you could see nearly 10 horsepower returned!