does anyone know how to tune the 1992 4ze1? seems to run like crap no matter what i do and only 160k on the clock? all hoses are good and distributor good. plugs new and throttle sensor new. that throttle body tho??? seriously wtf?. drives fine but backing down to idle and at idle it cant make up its mind what it wants to do?? gotta be something simple at such low kms?? getting sick of being jerked and jolted while trying to drive in town?