Hey guys, For those of you who have worked on their own cars I need some advice. I have a 1985 Mercedes Turbo Diesel 300D car and it has been working pretty good for me the last 4 years. Recently it has started to have problems with the starter which would need to be replaced. I will either purchase the part from eBay or get one from my dad and have a mechanic install it. However, this isn't the "only" problem with the car. My car is in pretty rough shape. The transmission and engine in the car were not the originals. The transmissions changes gears very roughly... but it has never had problems running in each gear... it just jerks a lot and has always done this. My brakes act funny sometimes. I changed the entire brake system so I know that a line and/or the master cylinder is still working correctly. I have had mechanics inspect it only to state that my brakes are just harder to push... indicating that the Power Booster is not working correctly. One tested the pressure in my power booster and said it was fine. Both of the problems above (transmission and brake booster) deal with the vacuum system. However, many mechanics/people have said diagnosing the vacuum system is very costly and hard to do. Fixing might solve these problems... I just don't know that much. Should I invest the time and money into repairing the vacuum system? I am willing to spend some time on it myself, I just don't know if anyone has had experience with this and is like it is not worth it at all. Can I have a mechanic show me how to fix it/give me advice for $$ and then I do it myself so that I can pay less? My car is really easy to work on, the parts are all very visible and what not. I've done quite a bit of work on it and have usually been very pleased... except for the braking system =[. What do you think? I can post more details if necessary.