Is their a way to retrieve trouble codes without a scanner.I have a "CHECK ENGINE" light ,and I do not have a OBD1 scanner.The car runs rough,fluctuating idle and will not pass smog inspection.The smog readings say the car has a HIGH HYDROCARBON reading.I am a mechanic on mainly diesel engines and equipment.I have done a complete tune up this vehicle,but the idle will not stabilize.HELP PLEASE.