The fuel filter is usually mounted to the right frame rail. Here's a photo from rockauto. Com to show what it looks like.
Idler pulleys often look like they're not turning because of the shiny black paint. It's easier to tell if there's a little dirt on it. You might consider sticking on a piece of tape or a wet leave, ... Anything to make it easier to see. Some designs include a large diameter stamped steel disc under the center bolt that does not spin. You have to look at the part the belt contacts. If the belt is indeed sliding over a locked up pulley, you should be hearing a severe squeal, have intermittent loss of power steering, or some other symptom. The belt would definitely start to smell and overheat. That smell would migrate into the vehicle after the engine was turned off.
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Tuesday, January 10th, 2012 AT 9:45 PM