2. Inspect Fuel Cut Off Rpm

1. Increase the engine speed to at least 3,500 RPM.
2. Use a sound scope to check for injector operating sounds.
3. Check that the operating sounds stop momentarily and then resume when the throttle lever is released.

HINT: 

Measure with the A/C OFF.

1. Fuel return RPM: 1,400 RPM 

Fig 1: Checking Injector Operating Sounds

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