Engine Mechanical problem
2000 Ford Focus 4 cyl Front Wheel Drive Automatic 96,000 miles
The engine is idleing very rough, especially when cold, smooths out some when warm. Sounds and feels like a diesel. Taken it to several shops and get back responses such as 'bad valves', 'emission problems'. But no one really seems to know. The car has not stalled and still performs pretty well on the highway. The car is not worth much (around $2k), so putting $1k in repairs when the technician is guessing does not make sense. A couple technicians just said " that's what these cars do after 96k miles". So, I'm trying to decide whether to continue trying to get it fixed, or give up and trade it in for something else.
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.