What will the K&N air filter do to my car?

If you are planning on keeping the stock cold air filter your car came with, that would be a good choice, if you like to clean your air filter every 25,000 miles or so. If you plan on trying to adapt a fake cold air filter kit or some type of short ram intake set up, I suggest you discuss this with your mechanic. For the most part, the cold air filter kits and short ram intakes to little to a stock motor, and there are many complaints online about ill fitting bolt on kits, and no place for important sensors, and check engine lights popping on. There are many complaints and questions for these power chips too, for most stock applications they are rated at wot or wide open throttle (this is true of the cold air filter and a power chip) you cannot run around town at wide open throttle, that is not going to help anything, and often a power chip does little more than advance timing, this can lead to premature valve wear, and a check engine light can lean out an engine, not what you want to happen. Anything you do that makes that engine work harder, will also help blow it up sooner.