FixItDaily
Active member
I have a 2003 Golf with Bosio 520 injectors, ported and polished head, stage II cam, VNT-17 turbo, and Kerma tuning. I recently put the new head on with the new cam and lifters because the head gasket let go. I also did ARP studs and a few other odds and ends. Car ran great for a couple of days, then it started having issues in first gear and only first gear. If I apply more than half throttle the car will lurch at about 2700 RPM, followed by a huge cloud of black smoke and then near zero power, the engine begins to chug loudly and at times it even dies. It eventually clears up and I’m off again. Car does fine in every other gear... I’m lost... I looked at vacuum lines, seems everything is in order. I did see an 3/4 inch bubble float through the fuel line when I had the hood up, made me think air, but it’s just strange it’s only in first gear. It also takes a sec to start when it’s cold, and runs rough for a few seconds. It didn’t do this before the head swap and stage II cam. The first time it happened I immediately thought it’d jumped a tooth on the timing belt so I shut the car off and inspected the belt, belt is tight and no teeth are missing. So I’m at a loss, could the timing be slightly retarded? So far I can’t find any answers, I found a thread that matched this but the owner had a 2004 car. I am not sure where to begin. I installed the head myself and I’m mechanically inclined, but I am not super familiar with this particular car. I got it to drive daily and have fun with... So far it’s blown a head gasket, left me stranded, tried to overheat... The list goes on and on. On another note cylinders and pistons looked great when I removed the old head and cylinder walls still had the hash marks. So internally it’s clean.