P2433Secondary Air Injection

Secondary Air Injection System Air Flow/Pressure Sensor Circuit Range/Performance (Bank 2)

The control module has detected that the secondary air injection air flow or pressure sensor on bank 2 is reporting a value that does not match expected performance. The secondary air system pumps air into the exhaust after cold start to help the catalyst heat up faster.

🚗 Yes, in most cases. It is an emissions fault that mainly affects cold-start emissions. Repair it to pass emissions testing.

MEDIUM

severity

🎯 Top Causes, Ranked by Likelihood

#1Faulty air flow/pressure sensor$80-$250

35%

The bank 2 sensor reports inaccurate flow or pressure values.

#2Failing secondary air pump$200-$500

25%

A weak pump produces flow outside the expected range.

#3Clogged air injection passages$100-$400

25%

Carbon buildup restricts flow into the exhaust, skewing the reading.

#4Wiring or connector fault$40-$200

15%

High resistance distorts the sensor signal.

🩺 Common Symptoms

Check engine light is on
Rough idle during cold start
Increased cold-start emissions
Air injection monitor incomplete

💰 Repair Cost: DIY vs Shop

DIY Cost

$80-$400

Shop Cost

$200-$600

📋 Free OBD2 Code Cheat Sheet

The 50 most common codes with likely cause and DIY fix cost. Sent once, no spam.

🔧 How to Diagnose P2433

1Inspect the bank 2 secondary air sensor connector and wiring.

2Command the secondary air pump on and observe flow and pressure data.

3Check air injection passages and hoses for carbon blockage.

4Replace the sensor or pump as indicated, then clear and retest.

❓ Frequently Asked Questions

How is this different from P2431?

It is the same fault on bank 2 rather than bank 1. Diagnosis and repair are the same.

Is it safe to drive?

Yes, in most cases. It mainly affects cold-start emissions.

Could carbon buildup cause this?

Yes. Clogged air passages are a common cause of range and performance faults.

🔗 Related Codes

P2434P2431P2442P0410P0491