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Air Injection: Testing and Inspection

Fig. 1 Testing reed valves B & C.:




Fig. 2 Reed valve A port D.:




Fig. 3 Reed valve A port E.:





1. Warm engine to normal operating temperature.
2. Place a thin piece of paper over inlet port of reed valve B and C, Fig. 1.
3. Increase engine speed to 1500 RPM and ensure air is being pulled in.
4. Increase engine speed to 3000 RPM and ensure there is no exhaust gas leaking from air inlet port.
5. If malfunction is found, replace reed valve.
6. Disconnect vacuum hose from No. 2 air control valve and plug it.
7. Place thin paper over inlet port D, Fig. 2, of reed valve A.
8. Increase engine speed to 1500 RPM and ensure air is being pulled in.
9. If air is not being pulled in, check No. 1 air control valve, then the reed valve.
10. Disconnect vacuum hose from No. 1 air control valve and plug it.
11. Apply 3.54 inches Hg of vacuum to No. 2 air control valve.
12. Place thin paper over inlet port E, Fig. 3.
13. Increase engine speed to 1500 RPM and ensure air is being pulled in.
14. If air is not being pulled in, check No. 2 air control valve, then the reed valve.
15. Stop engine and disconnect water temperature switch electrical connector.
16. Run engine at idle and ensure there is no vacuum at No. 2 air control valve vacuum hose.
17. Increase engine speed to 1500 RPM and ensure vacuum is present at vacuum hose.
18. If malfunction is found, check ACV solenoid valve.
19. Reconnect vacuum hoses to Nos. 1 and 2 air control valves.
20. Reconnect water temperature switch electrical connector.