Intake Manifold Leaks
An intake manifold air leak is characterized by lower than normal manifold vacuum. Also, one or more cylinders may not be functioning.
WARNING:
Use extreme caution when the engine is operating. Do not stand in a direct line with the fan. Do not put your hands near the pulleys, belts or the fan. Do not wear loose clothing.
- Start the engine.
- Spray a small stream of water (using a spray bottle) at the suspected leak area.
- If the engine RPMs change, the area of the suspected leak has been found.
- Repair as required.