Anti-Afterburn Valve Test

1. Disconnect air suction lower hose from anti-afterburn valve.
2. Start engine and quickly raise engine speed to 3500 RPM, then close throttle suddenly. Vacuum should not be present.
3. If vacuum is not present, proceed to step 6. If vacuum is present, check for voltage at anti-afterburn control solenoid valve.
4. If voltage is not present, check speed sensor for proper operation. If voltage is present, disconnect vacuum hose No. 31 from anti-afterburn valve and check for vacuum.
5. If vacuum is present, replace anti-afterburn valve and repeat test. If vacuum is not present, check for leaks or disconnected hose. If satisfactory, replace anti-afterburn control solenoid valve and repeat test.
6. Raise and support vehicle.
7. Start engine, then place selector lever in second gear or No. 2 position and accelerate. Suddenly release throttle and check vacuum during deceleration above mph.
8. If vacuum is present, test is complete. If vacuum is not present, check for voltage at anti-afterburn valve above mph.
10. If vacuum is present, replace anti-afterburn control solenoid valve and repeat test. If vacuum is not present, disconnect vacuum hose No. 30 from anti-afterburn valve and check for vacuum.
11. If vacuum is not present, check for leaks or disconnected hose and repeat test. If vacuum is present, replace anti-afterburn valve and repeat test.