Component Tests and General Diagnostics

1. Disconnect the vacuum hose (green stripe) from the throttle body, and connect a hand vacuum pump to the vacuum hose.
2. Plug the nipple from which the vacuum hose was disconnected.
3. When the engine is cold and hot, apply a vacuum while the engine is idling, and check the condition of the engine and the vacuum.

When engine is cold [Engine coolant temperature: 40°C (104°F) or less]

Hand vacuum Normal engine Normal vacuum
pump condition condition

Vacuum is No change Vacuum leaks
applied

When engine is hot [Engine coolant temperature: 80°C (176°F) or higher]

Hand vacuum Normal engine Normal vacuum
pump condition condition

40 mmHg (1.6 in.Hg) No change Vacuum is maintained
of vacuum is applied

200 mmHg (7.9 in.Hg) Idling becomes
of vacuum is applied slightly unstable