Wagoneer L6-258 4.2L VIN C 2-bbl (1982)
Air Injection Check Valve: Testing and Inspection
1. Check valves should be inspected whenever the hose is disconnected from the check valve or whenever check valve failure is suspected.
NOTE: An air pump that has shown any indications of having exhaust gases in the pump would indicate check valve failure.
2. Disconnect air supply hose from injection manifold, and listen and feel for exhaust leakage from check valve with engine running above idle.
Slight leakage is normal.