P0046 - TURBO / SUPER CHARGER BOOST CONTROL SOLENOID CIRCUIT RANGE / PERFORMANCE

The exhaust gases are used by the turbocharger to generate the turbine operation. There is an exhaust manifold, whose design is specially created to allow exhaust gases from the engine to enter the turbocharger from the turbine side. On the other side of the turbocharger there is a casing, which is coupled to the intake manifold by means of aluminum or silicone hoses. With this design, the turbocharger can capture the exhaust gases, compress them at high temperatures and return them to the engine as forced air induction.

Turbocharged and supercharged vehicles use forced air induction to increase engine performance. These engines require a very particular fuel delivery as well as an engine management strategy. That’s why PCM is programmed for those needs.

Importantly, there is a risk of engine damage due to excessive boost pressure. That is why there is a discharge valve that regulates the pressure. This pressure is relieved as the intake system is vented by a vessel designed for this purpose.

The discharge valve is controlled by a solenoid. If the PCM observes an over-impulse condition, a voltage signal is applied to the discharge valve solenoid, the valve opens and the excess exhaust pressure can escape. DTC code P0046 OBD2 is activated when the PCM detects a performance problem with respect to the impulse control solenoid.

• Check Engine light illumination on.
• Engine or transmission temperatures increase.
• Excessive amount of black smoke exits the exhaust.
• Cylinders may detonate due to high engine temperatures.
• Difficult acceleration.

The factors by which the fault code P0046 OBDII is established are:

• The Booster Pressure Sensor may be defective.
• Cables or connectors related to the discharge valve control solenoid may be defective.
• Valve solenoid may be defective.
• There may be leaks if the valve is vacuum controlled.
• Turbocharger failure.

To properly correct the diagnostic code P0046 OBD2 you must do the following:

• Consult Technical Service Bulletins (TSB).
• Check that the turbo system connections are correct. If you find problems with these connections, you must correct them.
• Make sure that the hoses, clamps and pipes of the intake system are in good condition. Repair or replace as needed.
• Using a bi-directional scanning tool order the control solenoid to change position to check its operation. Set the motor to 1,200 RPM and turn the solenoid on and off. When you do that the RPM should change and the PID position of the sensor should also change in the scanner. If the RPMs change, but the sensor PID does not, the Boost Pressure Sensor has problems.
• If the RPMs do not change, the problem is in the solenoid circuit or in the solenoid itself.