Common Symptoms
- Check Engine Light illuminated
- Reduced engine power or hesitation during acceleration
- Poor fuel economy
- Rough idle or engine surging
- Slight loss of low-end or mid-range torque
Most Likely Root Causes
- Faulty intake manifold tuning valve or actuator
- Damaged or corroded wiring to the tuning valve control circuit
- Failed intake manifold runner control solenoid
- Shorted control circuit or poor ground connection
- Failed powertrain control module (less common)
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Component Location
The intake manifold tuning valve is mounted on or inside the intake manifold assembly on Bank 2 (the cylinder bank opposite Bank 1).
Manufacturer Notes
Some manufacturers use variable intake manifold runner systems on Bank 2 that are prone to carbon buildup or actuator motor failure over time.
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