I recently bought a 04 WRX with 74,000 miles on it. The car is great and I love it. It seems that I get a ticking noise from under the hood on the drivers side of the vehicle. It's not loud but it's noticeable. The tick will increase as the RPMs increase but it disappears when the car is in neutral. Is this normal for a WRX or is it something that i should get checked out? What are some possibilities that could be causing this? FWIW the previous owner took great care of the car, it was never beat on or run hard. Any help would be great.