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Deceleration Valve: Testing and Inspection

Fig. 32 Deceleration Valve:





1. In order to operate correctly, the deceleration valve hoses must be in good condition and free of internal restriction.
2. Disconnect the vacuum line at the deceleration valve.
3. Disconnect the air inlet hose from the intercooler.
4. Blow air through the hose. Deceleration valve should be closed and air stream must be blocked.
5. Connect a vacuum pump to the deceleration valve vacuum connection. Apply vacuum with vacuum pump. Verify that system holds the applied vacuum (no bleed-off).
6. Blow air through the air inlet hose. Deceleration valve should be open and air must flow freely into the intake system.
7. If deceleration valve fails the test, replace and retest with new valve.
8. Disconnect test equipment and reconnect all hoses.