Secondary air supply system uses a pulse action design. Primary components of the system are the secondary air control valve, secondary air control solenoid valve and a reed valve. Reed valve is actuated by exhaust vacuum being generated from pulsation in the exhaust manifold.
Based on sensor information, the ECU will energize the secondary air control solenoid valve. When energized, the solenoid valve opens to allow manifold vacuum application to the secondary air control valve. When vacuum is applied to control valve diaphragm, secondary air circuit is open and system is activated. The secondary air circuit system is used to direct secondary air into the exhaust system near the catalytic converter.
CARBURETED
- Disconnect air supply hose(s) from air cleaner. Start engine and warm to 68-104°F (20-40°C). There should be suction at air hose(s) at idle. When engine temperature is 158°F (70°C) or more, there should be suction (at idle) within 70 seconds after starting engine. After 70 seconds, there should be no suction. Accelerate engine to 4000 RPM and as engine is decelerating, there should be suction at air hose(s).
- If these conditions are met, secondary air supply system is good. Replace secondary air control valve assembly and reed valve if exhaust gases blow out of air hose.
TURBOCHARGED
- On Colt and Conquest, connect a 1/2" O.D. hose to secondary air cleaner intake hose.
- On all models, start engine and warm to 104-140°F (40-60°C). There should be suction at hose at idle. When engine temperature reaches 158°F (70°C) or more, there should be no suction. Accelerate engine to 4000 RPM and as engine is decelerating, there should be suction at air hose.
- If these conditions are met, secondary air supply system is good. Replace reed valve if exhaust gases blow out of air hose.
SECONDARY AIR CONTROL VALVE
- Remove valve and blow in air from air cleaner side. Air should not blow through. Connect a vacuum pump to valve nipple. Apply 19.8 in. Hg of vacuum. Vacuum should hold.
- Apply 6.0 in. Hg of vacuum to valve. Air should blow through from air cleaner side to exhaust manifold side. Air should not blow through in opposite direction. If results are not as specified for any test, replace secondary air control valve.
- Remove White-striped and Green-striped vacuum hoses from solenoid valve. Separate harness connector. Connect vacuum pump to nipple where White-striped hose was connected and apply vacuum.
- When battery voltage is applied to valve and other nipple is left open, vacuum should leak. If nipple is plugged, vacuum should hold.
- When no voltage is applied and nipple is left open, vacuum should hold. Measure solenoid coil resistance. Standard value is 38-44 ohms.
- Remove White-striped, Blue-striped and Yellow-striped vacuum hoses from solenoid valve. Separate harness connector. Connect vacuum pump to nipple where White-striped hose was connected and apply vacuum.
- When battery voltage is applied to valve, vacuum should leak. When no voltage is applied, vacuum should hold.
- Connect vacuum pump to nipple where Blue-striped hose was connected and apply vacuum. When battery voltage is applied to valve, vacuum should hold. When no voltage is applied, vacuum should leak. Measure solenoid coil resistance. Standard value is 38-44 ohms.
- Disconnect air hose from reed valve. Connect a 1/2" O.D. extension hose to secondary air cleaner air intake port. Disconnect Yellow-striped vacuum hose from secondary air control solenoid valve. Connect a vacuum pump to hose end.
- Apply 19.8 in. Hg of vacuum. Vacuum should hold. With no vacuum applied, blow in air from end of extension hose. Air should not blow through. Apply 6.0 in. Hg of vacuum and blow in air. Air should blow through.
