I just got a '99 A4 1.8t. It's got all the service records - consistent 3k mile synthetic oil change, 60k tuneup, etc. - and was owned by a pretty cool guy who took great care of it. The only problem with this is that when I shift up a gear, in either auto or tiptronic mode, it seems like the clutch slips a little and the RPMs go a couple hundred up, then it feels like it catches fine and the RPMs slide down to where they should be and then it's fine. That little slippage business only happens for about 2 seconds and then it's running like normal. All that I know about this kind of thing is that in my old 6-speed Maxima I had a similar clutch slippage type of issue and upgraded the clutch to solve the problem. Any info and/or suggestions as far as a remedy for this would be appreciated. I've also purchased some basic upgrade parts like Denso Iridium plugs, Zimmerman front rotors, Metal Matrix pads all around, K&N drop-in filter, engine snub mount, ATE super blue brake fluid, and that Bosch N71 or something bypass valve that pre-'02s are supposed to get. I'd like to get a turbo-back exhaust soon, as well springs and/or shocks, so if you have any personal recommendations for those i'd appreciate it as well. And if there are some more fairly inexpensive things that I should consider having done, please let me know. Thanks in advance.