Hi Everyone,

I've exhausted my internet research and unfortunately I am no closer to locating an answer than when I first began, yet hopefully you guys can help me reach the truth!

I have an 04 Xfire manual with about 89k miles. For about a month now the engine has been making a knocking noise. The following video I found illustrates the exact noise my car is making:
One of the comments suggests that its the water pump and the idler pulley, could this be? Seems odd to me.

I believe the nosise is coming from the passenger side of the vehicle. The knocking does not seem to grown when I accelerate, and is most noticable when the engine is idle. I recently switched the engine oil to a thicker grade 0-40w (mechanic recommendation) and the only change this did was to have the noise dissipate for the first minute or so that the engine is on, then the noise comes back.
I have no noticeable performance issues. I performed a maintenance checkup about a year ago and spark-plugs were changed.

Please Help!