D 250 Pickup V8-5.9L VIN Z (1992)
Air Injection Pump: Testing and Inspection
GENERAL INFORMATION
For satisfactory emission control and engine durability, air pump must be operating at all times (except when performing diagnosis tests). To be
sure of proper operation of air pump, pump drive belt should be in good condition and adjusted to specified tension. Inspect the condition of air
pump belt and adjust belt tension to specifications.
Air pump service involves replacing either the centrifugal fan filter or the entire pump. Do not disassemble pump for any reason. Do not clamp
pump in a vise or use a hammer or pry bar on the pump housing.
