Volkswagen Repair: cylinder misfires, mass airflow sensor, cylinder compression

Question
I have an 01 jetta 1.8t. cylinders 2 and 3 were misfiring. we replaced the spark plugs with ngk ones. and all new coil packs. also replaced the mass airflow sensor. we changed the packs from cylinders 2 and 3 to the outsides, thinking it would be a faulty coil. then the computer detected cylinders 1 and 2. which leads me to think that maybe the fuel injector is messed up on 2 and one has another problem such as a faulty coil beings that was the only change we made. and ideas??

Answer
You're on the right track.  The only additional items that would cause consistent misfires on particular cylinders are wires, cap/rotor, injectors, or cylinder compression.  Otherwise, timing and fuel pressure could cause general rough engine performance.  Also various sensors can cause issues, but these would normally have been revealed by an OBD scan.