As for the vibration it may be a CV joint or wheel bearing...94 is not OBD1.5 95 is....You have OBD1 and any obd1 scanner of ability can pull the codes (ses light) Otherwise you can use a paperclip to jump terminal a and b on the port and read the codes that way..By watching the number of flashed...Will explain more if need be..But welcome to the forum we love pics and if you start a thread in the proper section we can assit you further as well as it will be veiwed by more members!
2000 Suburban 3" lift and some power mods..The daily
06 impala SS CAI,Exhaust,pirellies the other daily
86 camaro Far from stock......The hot rod
1992 camaro RS 25th anv 350 5 spd..The cruiser