All right young fella, I'm gonna tell you, like I end up tellin' many of my customers (I manage a repair shop), DON"T spend a nickle on the car till ya have it diagnosed by a TRUSTED professional. That's because you'll likely be throwing your $$$ away changing un-needed parts yourself. I see this happen EVERYDAY !!!
So...go spend a little $$ finding out what the CAUSE of the problem is, before replacing parts. You may be able to replace the CORRECT part yourself, thus saving $$$ that way.
Most of the time, the customer has changed several items either they, or their buddy, THINKS is the the problem. Then they come in and we figure it out for them, but NOW they don't have enough $$ to get it properly fixed.
They end up kicking themselves for not getting it diagnosed first. They try and justify all those parts by saying "well it didn't hurt going ahead and replacing the water pump, or thermostat, or radiator, etc. But it did hurt, right in the wallet!!!