Granted Ford Focus may not be the most robust cars out there, but I don't think 96,000 miles equal to the end of the car's life. When a car runs rough at idle but runs okay at higher speed, it usually indicates a vacuum leak (not always though).
Do you have any codes? (Engine light on?) If so post back with it/them and we can start from there. Some auto part stores scan your car for free.
By the way, what the different mechanics told you are all possibilities (bad valve, exhaust problem). If the technicians are just guessing though, you should find a different shop. Shot gunning parts at a car is not a good technique.
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Friday, May 1st, 2009 AT 11:16 AM