Intake Manifold Tuning Valve Diagnosis

Intake Manifold Tuning Valve Diagnosis:

Intake Manifold Tuning Valve Circuit:

CIRCUIT DESCRIPTION
The control module activates the intake manifold tuning valve during acceleration when engine speed exceeds 3000 RPM and throttle position is greater than 34%.
The control module energizes the intake manifold tuning valve by grounding the intake manifold tuning valve relay control circuit. The energized relay coil closes the relay contacts allowing current flow through the relay to the intake manifold tuning valve solenoid.

TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.

1. This step determines if the system is functioning at the present time.

2. By cycling the tuning valve "ON" and "OFF" will determine if the tuning valve relay is operating.

3. This will determine if the tuning valve relay has ignition voltage on ignition feed circuit.

4. This step will determine if the relay related wiring to valve or the tuning valve is at fault.

5. This step will determine if the control module tuning valve relay or related wiring is at fault.


DIAGNOSTIC AIDS
An intermittent Throttle Position Sensor (TPS) output will cause the control module to receive a false input.