i noticed that my 2011 wrx starts to sputter at lower rpms once in a while. and i also began to notice that when i give the car gas and release the engine temp drops a bit and then goes back to normal. is this normal for the temp guage to move like that during driving? and the sputtering goes away if i give it gas. the sputtering happens when i keep a consistant rpm i have to give it a little gas to make it stop. what the hell is going on with the rex any advise thanks in advance.