Intake Manifold Vacuum: Inspection

Navigate to the service mode (for exhaust gas measurement). (Hybrid model) Ref. to P-HEV HYBRID POWERTRAIN CONTROL (DIAGNOSTICS)>WORK SUPPORT>OPERATION>SERVICE MODE .
NOTE: If it is necessary to run the engine for 10 minutes or more, fasten the driver's seat belt.
Warm up the engine.

Disconnect the brake booster vacuum hose from the intake manifold assembly. (Gasoline engine model)

2.0 L model

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2.5 L model

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Disconnect the vacuum hose from intake manifold assembly. (Hybrid model)

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Connect the vacuum gauge to the brake booster vacuum hose installation position (gasoline engine model) or vacuum hose installation position (hybrid model) of the intake manifold assembly.

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Navigate to the service mode. (Hybrid model) Ref. to P-HEV HYBRID POWERTRAIN CONTROL (DIAGNOSTICS)>WORK SUPPORT>OPERATION>SERVICE MODE .

Keep the engine at idle speed and read the vacuum gauge indication.

NOTE: Condition of engine inside can be diagnosed by observing the behavior of the vacuum gauge needle as described in table below.

Diagnosis of engine condition by inspection of intake manifold vacuum
Vacuum gauge needle behavior	Possible engine condition
1. Needle is steady but lower than standard value. This tendency becomes more evident as engine temperature rises.	Leakage around intake manifold gasket, disconnection or damage of vacuum hose
2. Needle intermittently drops below the standard value.	Leakage around cylinder
3. Needle drops suddenly and intermittently from the standard value.	Sticky valve
4. When engine speed is gradually increased, needle begins to vibrate rapidly at certain speed, and then vibration increases as engine speed increases.	Weak or broken valve springs
5. Needle vibrates above and below the standard value in narrow range.	Defective ignition system

Intake manifold vacuum (A/C is OFF (gasoline engine model) and at idling):

Standard

-60.0 kPa (-450 mmHg, -17.72 inHg) or more