Engine light (code P0520)

This code is for your oil pressure sensor switch. It only cost about 20 bucks. It's not really going to harm your engine if you don't fix it right away (unless you have oil pressure issues), but I just replaced mine and thought I would share the knowledge. I have seen a few videos saying to remove the alternator which is a hassle and completely unnecessary. This is what you need to do.
1. Loosen the belt using the tensioner pulley, and remove the upper radiator hose.
2. Take the wiring harness off of the existing switch. This may be slightly difficult due to a red sliding tab you have to move all the way to one side.
3. Buy a 27mm deep socket and unscrew the existing sensor. I tried for at least and hour to unscrew it with a vice grip and pliers. Just go buy the socket because it is in there good and has Loctite on it.
4. Install the new sensor ensuring to be careful not to break the plastic side where the harness connects (saw a guy do it on youtube). You have to give a little effort in screwing it in all the way because the new on comes with Loctite as well.
5. Reinstall the harness making sure to slide the red tab back, and then reassemble the belt and radiator hose.

After doing this once I could probably get it done in 10 minutes. The only pain in the but is how cramped it is with the alternator on, but it's not worth the trouble to remove it. Hope this helps someone!