Faulty Intake Valve Control Solenoid Bank 1
Intake Valve Control Solenoid Bank 1 harness is open or shorted
Intake Valve Control Solenoid Bank 1 circuit poor electrical connection
Engine Light ON (or Service Engine Soon Warning Light)
The intake valve timing control solenoid valve is activated by ON/OFF pulse duty (ratio) signals from the Engine Control Module (ECM).
The intake valve timing control solenoid valve changes the oil amount and direction of flow through the intake valve timing control unit or stops the oil flow.
The longer pulse width advances valve angle. The shorter pulse width retards valve angle. When ON and OFF pulse widths become equal, the solenoid valve stops oil pressure flow to fix the intake valve angle at the control position.