the check engine light went on with a code of p0505.we change the throttle body on 1997 Mitsubishi Galant

new idle aircontrol motor. changed the hose to the EVAP solenoid and EGR solenoid. change spark plugs and wires, but it still idles irracticly when in park or neutral. took it to pete boys but all they say is it has vacuum leak. what do we do

Asked by for the 1997 Mitsubishi Galant
have a mech do a smoke test to determine cause of leak. stay away from pep boys for this