Diagnostic Procedure
- Operate engine until it reaches normal operating temperature.
- Disconnect engine vacuum harness from vacuum pump inlet pipe.
- Connect Valve Manometer (J 23951), or vacuum gauge, to vacuum pump inlet pipe.
- Operate engine at an idle for 30 seconds. If engine operates for longer than 30 seconds, or if engine does not operate at an idle, vent manometer and repeat this step.
- While operating engine, observe manometer reading. Reading should be within specification. See VACUUM PUMP SPECIFICATIONS table.VACUUM PUMP SPECIFICATIONS
Elevation - Ft. Minimum Specification - In. H2 O (kPa) Zero 21 (-70) 5000 18 (-60) 10,000 14 (-49) 15,000 12 (-40) - If vacuum pump fails to meet minimum specifications, replace vacuum pump and retest