Mitsubishi Repair: my 91 eclipse has idle and shifting problems, mass air sensor, eclipse gs

Question
i just bought a 1991 eclipse gs with an aftermarket turbo, problem is when its at an idle it revs up the rpms from 1100 to 1700 or so, so any time i give it gas it does this, help me out thanks  

Answer
Dustin,
This could be happening due to a faulty mass air sensor, a faulty Idle Air Controller, or just an improperly adjusted idle speed. With your engine at normal operating temperature, your idle should be around 750 RPMs (plus or minus 50).  If you get a service manual for your car, it'll give simple procedures to check those items.  Most major auto parts stores will carry a service manual for your car for around $10-$15.
Good luck!