Figured out my really rich issue with my 1987 alfa spider that a bought awhile back and just got on the road the last 2 days. The car had a stuck open injector causing the car to run rich and I replace the faulty injector and the car runs well now with good power however my idle now goes up and down and wanted to know where to start. My o2 sensor is new and I believe my MAF to be in good working shape and the car has new wires, plugs, rotor and cap. I checked all my hose connections and everything seems to be tight. Would the idkle control valve do this or do you guys think that I have an air leak somewhere/ The car runs well throughout the rpm range just has an idle up and down issue. Any help would be appriciated.