P2433 OBD-II Trouble Code: Secondary Air Injection System Air Flow/Pressure Sensor Circuit High Bank 1

Diagnostic Trouble Code (DTC): P2433

P2433 code definition

Secondary Air Injection System Air Flow/Pressure Sensor Circuit High Bank 1

Related Trouble Codes:

• P2430: Sec Air Inj Sys Airflow/Press Sensor Circ Bank 1
• P2431: Sec Air Inj Sys Airflow/Press Sensor Circ Range/Perf Bank 1
• P2432: Sec Air Inj Sys Airflow/Press Sensor Circ Low Bank 1
• P2434: Sec Air Inj Sys Airflow/Press Sensor Circ Interm/Erratic Bank 1
• P2435: Sec Air Inj Sys Airflow/Press Sensor Circ Bank 2
• P2436: Sec Air Inj Sys Airflow/Press Sensor Circ Range/Perf Bank 2
• P2437: Sec Air Inj Sys Airflow/Press Sensor Circ Low Bank 2
• P2438: Sec Air Inj Sys Airflow/Press Sensor Circ High Bank 2
• P2439: Sec Air Inj Sys Airflow/Press Sensor Circ Interm/Erratic Bank 2
• P2440: Sec Air Inj Switching Valve Stuck Open Bank 1
• P2441: Sec Air Inj Switching Valve Stuck Closed Bank 1
• P2442: Sec Air Inj Switching Valve Stuck Open Bank 2
• P2443: Sec Air Inj Switching Valve Stuck Closed Bank 2

What the P2433 code means

The P2433 diagnostic trouble code is an indication that there is a problem with the airflow/pressure sensor circuitry of the secondary air injection system.

The secondary air injection system allows fresh air into the exhaust system. The purpose of this is to reduce the amount of harmful pollutants that the exhaust emits into the environment. The secondary air injection system sends a voltage signal to the powertrain control module (PCM). This voltage signal contains information regarding the pressure and flow of the secondary air injection system.

If the voltage signal reading exceeds the specifications that have been predetermined by the manufacturer, the P2433 diagnostic trouble code will be set by the PCM and the Check Engine Light will come on.

What causes the P2433 code?

• Faulty air injection valve
• Faulty one-way check valve
• Faulty air injection pump
• Faulty pressure sensor
• Pressure sensor wiring that is frayed, broken, or shorted
• Pressure sensor connector that is damaged or corroded
• Pressure sensor connector that has bent pins
• Faulty vacuum switching valve
• Vacuum switching valve wiring that is frayed, broken, or shorted
• Vacuum switching connector that is damaged or corroded
• Vacuum switching connector that has bent pins

What are the symptoms of the P2433 code?

• Check Engine Light is on
• Secondary air injection system may be noisey
• Engine may stall when idling
• Engine may stall when starting the vehicle
• Engine may hesitate when accelerating
• P2440 diagnostic trouble code stored in the PCM

How does a mechanic diagnose the P2433 code?

• Uses an OBD-II scanner to collect freeze frame data and all the trouble codes that have been stored by the PCM

• Inspects vacuum switching valve wiring for frays, breaks, and shorts (repairs and replaces as required)

• Inspects vacuum switching valve connector for damage, corrosion, or bent pins (repairs and replaces as required)

• Clears all diagnostic trouble codes from the PCM and operates the vehicle for complete a test drive to see if the P2433 trouble code comes back

• Inspects pressure sensor wiring for frays, breaks, and shorts (repairs or replaces as required)

• Inspects pressure sensor connector for damage, bent pins, and corrosion (repairs or replaces as required)

• Clears all diagnostic trouble codes from the PCM and operates the vehicle for complete a test drive to see if the P2433 trouble code comes back

• Inspects the one-way check valve to ensure it is working properly (repairs or replaces as required)

• Clears all diagnostic trouble codes from the PCM and completes a test drive to see if the P2433 trouble code comes back

• Inspects the air injection pump to ensure that it is working properly

• Inspects the air injection pump hoses for breaks and loose connections (repairs or replaces as required)

• Inspects the air injection system fuses.

• Inspects for damaged wiring or pumps that are causing a blown fuse (repairs or replaces as required)

Common mistakes when diagnosing the P2433 code

It is important to test the one-way check valves before making a diagnosis for the P2433 trouble code. Faulty one-way check valves are a common diagnosis for the P2433 trouble code so neglecting to test them could lead to a misdiagnosis and multiple secondary air injection pump replacements. When replacing the secondary air injection pump, it is important to add a drain tube onto the pump housing. Failing to do so could cause multiple secondary air injection pump failure.

How serious is the P2433 code?

The P2433 diagnostic trouble code is considered serious. Several symptoms of the P2433 trouble code could make driving conditions extremely hazardous. Therefore, it is important to have this trouble code diagnosed and repaired as soon as possible.

What repairs can fix the P2433 code?

• Replacing faulty air injection valve
• Replacing faulty one-way check valve
• Replacing faulty air injection pump
• Replacing faulty pressure sensor
• Repairing or replacing frayed, broken, or shorted pressure sensor wiring
• Repairing or replacing damaged or corroded pressure sensor connector
• Repairing or replacing bent pins in the vacuum switching connector
• Replacing faulty switching valve
• Repairing or replacing frayed, broken, or shorted vacuum switching connector
• Repairing or replacing melted, or corroded vacuum switching connector
• Repairing or replacing bent pins in the vacuum switching connector

Additional comments for consideration regarding the P2433 code

It is common for faulty one-way check valves to cause the P2433 diagnostic trouble code. Testing them prior to making a diagnosis is important to ensure a proper diagnosis. Failing to diagnose and replace faulty one-way check valves could cause other components of the secondary air injection system to become damaged.

Need help with a P2433 code?

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