OBD-II Code P2430 — What It Means & How to Fix It

What it means

The secondary air injection (SAI) system pumps fresh air into the exhaust during cold starts to burn off excess hydrocarbons and heat up the catalytic converter faster.
P2430 means the pressure or air flow sensor in this system on Bank 1 has a fault — the system can't verify proper air flow is reaching the exhaust.
This results in higher cold-start emissions and a check engine light.

Affected Models

All vehicles 1996+ with secondary air injection
Common in BMW vehicles
Common in Mercedes vehicles
Common in Toyota and Lexus vehicles
Common in Volkswagen and Audi vehicles

Common Causes

Failed secondary air injection pressure sensor
Clogged secondary air injection passages from carbon buildup
Failed secondary air injection pump not producing air flow
Cracked or disconnected air injection hose losing pressure
Damaged wiring to the pressure sensor

How to Fix It

Check for companion codes — P0410, P0411 help narrow down the exact fault.

P0410 points to the pump itself; P0411 suggests air is reaching the wrong place — use these to guide your diagnosis.
Inspect SAI hoses and connections for cracks or disconnections.

Rubber SAI hoses crack with age and heat — a cracked hose will cause a pressure drop that triggers the sensor code.
Listen for the SAI pump running during cold start — if silent, the pump may have failed.

During the first 60–90 seconds of a cold start, you should hear a faint whirring from the SAI pump under the hood.
Test the pressure sensor wiring and connector for damage.

Damaged wiring to the sensor causes false pressure readings — check for chafing near the exhaust manifold where heat is highest.
Replace the pressure sensor or SAI pump based on testing results.

If the pump runs but produces no pressure, it has failed internally — water ingestion is the most common cause of SAI pump failure.

When to Call a Professional

If the SAI pump runs but P2430 persists, have a mechanic test the pressure sensor circuit and air flow output.
Diagnosis involves measuring sensor voltage during a cold-start SAI activation and checking for passage blockages.
Expect $100–$200 for diagnosis; pressure sensors cost $30–$100, while SAI pump replacement runs $150–$400.

Frequently Asked Questions

What does the secondary air injection system do?

It injects fresh air into the exhaust during cold starts.
This burns off unburned hydrocarbons quickly and warms the catalytic converter faster.
It only runs for the first minute or two after a cold start.

Can I drive with P2430?

Yes, but cold-start emissions will be higher than normal.
You will fail an emissions test.
Fix it at your next opportunity.

How long do secondary air pumps last?

Most last 80,000–120,000 miles.
Water intrusion is a common killer — many pumps fail when water is sucked in during puddle driving.