Component Tests and General Diagnostics

Manifold Vacuum Check
1. Start the engine and allow it to warm up until the temperature of the engine coolant reaches 80 - 95°C (176 -203°F).
2. Connect a tachometer.





3. Attach a three-way union to the vacuum hose between the fuel pressure regulator and the intake manifold plenum, and connect a vacuum gauge.
4. Start the engine and check that idle speed is within specification. Then check the vacuum gauge reading.
Idle speed: 750 ± 100 r/min
Minimum limit: 60 kPa (18 inch Hg).