Hello fellow mk 4 owners and mechanics. I have a 2001 gti vr6 that I recently had the timing chain replaced on. When I picked it up from the mechanic it had the feeling of a misfire happening in 1st, 2nd, 3rd. My mechanic changed the plug wires, spark plugs, and even tried a new ignition coil. This helped the problem but did not fix it completely. It is still slightly there in first and you can feel it mostly in second accelerating under load between 2000 and 3400 rpm's. It is difficult to get it to do in third which is strange. My mechanic also put a new fuel pump and filter in it, and checked the MAF sensor. The problem is it is not tripping a code, so it is all guess work. The only other ideas I have are to replace the fuel pressure regulator or maybe it is a vac hose leak or something. Has anyone else had anything like this? it feels like a little bog that happens three or four times before you hit 32-3400 rpms, then the engine pulls really strong. Mechanic can't figure out why it is mosly only in first and second, and strongest in second. Any ideas would be greatly appreciatted. The car checks out absolutely clean when checked out with the computer so I am getting a little frustrated.
PS, He is a good mechanic - he did all the ignition and fuel line stuff for free, he wants to fix it as bad as I do. He trained at the euro car school in Ireland and worked for Mercedes for a number of years. He is a good guy, so that is not the problem.
Thanks in advance.