04 GTI VR6 with 103k with a misfire on cylinder #2. Flashing check engine light and stuttering under moderate acceleration. I changed the plugs at 80k, coils are original. I assumed this was a blown coil so I replaced it, and ran bottle of Chevron Techron through tank and issue remains. Question now is whether this is a bad plug or bad fuel injector? Search seems to indicate it could be either, looking for opinions on diagnosis. Any help is appreciated.
Swap the coil & plug from cylinder #2 with a coil & plug from another cylinder, and see if the misfire follows it or stays with cylinder #2.
If it follows, then it's a faulty coil or plug. If fault stays with cylinder #2, look at the injector.
Also check your coil wiring/connector isn't damaged/dirty. Could just be a bad connection (maybe unlikely, but it's quick and easy to check).
This exact problem happened to me a few weeks ago. Stopped to get gas. Started the car and bam! Check engine light and bad stuttering / loss of performance. DTC was for misfire on cylinder #2. Had to get it towed to a VW dealership. They found 1 bad ignition coil and 1 bad connector. I would say, like turbo4motion said, change the coils around and see if the problems go to another cylinder. If that is the problem, replace the ignition coil. I ended up changing the other five after the dealership was done with it because being stranded sucks. This is the cheapest place I could find them at, and is where I ordered mine from. http://www.carpartsshed.com/Catalog/...6%20Cyl%202.8L