Mitsubishi Repair: my 95 mitsu mirage coupe 1.8 [4g93] 5 speed , revs itself between 1k &2k rpm, mirage coupe, adjustment terminal

Question
I screwed this bolt all the way tite on the top of the throttle body near the manifold i was thinking it was the isc adjustment , i think it got rid of the problem , but now my car slightly shakes when at rest and i never had this problem before i twisted this bolt , Even if it was the ics adjust??

Answer
Aaron,
That is the base idle setting screw (BISS).  It's meant to adjust your curb idle speed.  This should only be adjusted with both the ignition timing adjustment terminal and ECU grounded.  If you turn it without grounding those items, you will have problems like poor idle; like the one you described.  You now need to re-adjust it the proper way for your engine to idle properly.
Good luck!