Emission Control Systems: Testing and Inspection

Anti-Afterburn Valve
1. Start and operate engine at idle.
2. Close off air intake port of the anti-afterburn valve and ensure engine speed does not change.
3. Increase engine speed and quickly decelerate. Air should be sucked into the intake port for 1 to 2 seconds after the accelerator is released. If air is not sucked into the intake port, replace anti-afterburn valve.

Servo Diaphragm

WAGON
1. Connect tachometer to the engine.
2. Run engine until it reaches normal operating temperature and ensure idle speed is within specifications, then turn off engine.
3. Disconnect vacuum hose between servo diaphragm and No. 1 three-way solenoid valve at servo diaphragm.
4. Using suitable vacuum hose connect inlet manifold and servo diaphragm
5. Start engine and increase engine speed to 2000 RPM with throttle lever.
6. Release throttle lever and ensure engine speed is 1100 to 1300 RPM.
7. If engine speed is not within specifications turn throttle positioner adjusting screw in or out until specified engine speed is obtained.

Exc. Wagon
1. Connect a suitable tachometer to the engine.
2. Operate engine and ensure engine idles properily. Switch engine off and remove air cleaner.
3. Disconnect vacuum hose from servo diaphragm. Connect a suitable vacuum hose between intake manifold and servo diaphragm. Start engine and increase engine speed to 2000 RPM with throttle lever, then release throttle lever and ensure engine speed is 1100 to 1300 RPM, adjusting as necessary

Engine Speed Unit

EXC. WAGON
1. Connect voltmeter to engine speed unit electrical connector.
2. Increase engine speed to 3000 RPM, then slowly decrease engine speed and record RPM at which current does not flow to circuit. This should be 2000 to 2200 RPM.
3. Increase engine speed to 2000 RPM, then slowly decrease engine speed and record engine speed at which current flows to circuit. This should be 1430 to 1570 RPM.
4. If test results are unsatisfactory, replace engine speed unit.

WAGON
1. Connect voltmeter to electrical connector of engine speed unit
2. Increase engine speed to 2000 RPM, then slowly decrease engine speed and record engine speed at which current flows to circuit. This should be 1430 to 1570 RPM.
3. Increase engine speed to 2500 RPM, then slowly decrease engine speed and record engine speed at which current does not flow to circuit. This should be 2000 to 2200 RPM.
4. If test results are unsatisfactory, replace engine speed unit.

Three Way Solenoid Valve

EXC. WAGON
1. Disconnect vacuum hose between No. 1 three-way solenoid valve and servo diaphragm at servo diaphragm.
2. Disconnect other vacuum hose at No. 1 three-way solenoid valve.
3. Disconnect electrical connector of No. 1 three-way solenoid valve.
4. Blow air into hose still connected to No. 1 three-way solenoid valve and ensure air blows from open port of valve.
5. Apply battery voltage to electrical connector of No. 1 three-way solenoid valve.
6. Blow air into hose still connected to No. 1 three-way solenoid valve and ensure air flows from air fitter of valve.
7. If test results are unsatisfactory, replace No. 1 three-way solenoid valve.

WAGON
1. Disconnect vacuum hose between No. 1 three-way solenoid valve and servo diaphragm at servo diaphragm.
2. Disconnect vacuum hose between No. 1 three-way solenoid valve and inlet manifold at No. 1 three-way solenoid valve.
3. Disconnect electrical connector from No. 1 three-way solenoid valve and ground valve with jumper wire.
4. Turn on ignition switch.
5. Blow air into hose still attached to No. 1 three-way solenoid valve and ensure air flows from air filter of valve. 6 Turn ignition switch off.
6. Turn ignition switch off.
7. Blow air into hose still attached to No. 1 three-way solenoid valve and ensure air flows from open port of valve.
8. If test results are unsatisfactory, replace No. 1 three-way solenoid valve.