BCDD Operating Pressure
- To check pressure, engine should be at normal operating temperature, idle speed set to specifications and transmission in Neutral. Connect a tachometer to engine and a vacuum gauge to intake manifold.
- Run the engine under no load and note vacuum reading. Increase engine speed to 3000-3500 RPM on Maxima, or 2000 RPM on Pickup, then quickly close the throttle.
- Manifold vacuum should increase 23.6 in. Hg or more on Maxima, or 24.0 in. Hg or more on Pickup. Gradually decrease to idle level. Operating pressure should be 21.6-23.2 in. Hg on Maxima and 23.8-24.2 in Hg. on Pickup. If pressures at idle are not to specification, proceed to ADJUSTMENTS .