Mazda Repair: 2.5 Mazda engine (*in ford contour lx), air control valve, ford contour

Question
I have a brrrr sound when I tap the gas pedal. It only appears when the car is warmed up. the brrring sound changes to a sound like a loose pulley or a fan blade touching the radiator sometimes. other times I can't make it make a noise at all.  I replaced the belt tensioner at a shop this summer. I don't want to think it is a spun bearing. Tell me it only a harmonic balancer problem! Glen

Answer
thats an easy one glen.. your iac valve is hanging up. i would reconmend changing it,  it's not really exspensive.  if you give it a good rap with a light hammer it will go away for a bit.  iac-  idle air control valve- facing the engine, it's on the right side of the intake towards the rear. it's really easy to change, all you will need is a 8mm and a 10mm 1/4 inch deep socket,  dont loose the metal gasket cause it will drop down.  you can re-use the gasket.