P0410: Secondary air injection system fault
Secondary air injection system malfunction
Severity: Monitor
P0410 is an emissions-system fault: the car has an air pump that helps clean the exhaust right after a cold start, and it usually drives normally without it.
It gets more serious if:
- Inspect soon: Have it checked soon if there are starting difficulties, hesitation or a loud pump noise, which MechanicBase lists as possible symptoms.
P0410 in short
P0410 means the engine computer commanded the secondary air injection system and did not see the expected result. A failed air pump, a bad check or switching valve, or a blown fuse or relay is most common. The car is usually driveable, but it will fail an emissions test.
Secondary air injection blows fresh air into the exhaust during a cold start so unburned fuel burns off before the catalytic converter is warm. The computer then watches the oxygen sensors for the change it expects.
If the air does not arrive or the oxygen sensors do not respond, it sets P0410. Rick's advises testing during a true cold start, because the system only runs then; on a warm engine it looks dead.
Failures include the pump (water, worn bearings), carbon-clogged passages, a stuck valve, a failed check valve, and plain electrical faults such as a fuse or relay.
Most likely causes
Cause 1: Blown fuse, bad relay or wiring fault to the air pump
Common general cause- Why it ranks here
- MechanicBase says to check the fuse, connections and hoses before replacing expensive parts, and Rick's lists fuses, relays and corroded connectors.
- What would change this
- Rises if the fuse is blown or the pump gets no power at cold start. Falls if the pump has power and ground and still does not run.
Cause 2: Failed secondary air pump
Common general cause- Why it ranks here
- Both sources list the pump first: motor failure, worn bearings or water inside.
- What would change this
- Rises if the pump gets power but does not run or is noisy. Falls if it runs and air reaches the exhaust.
Cause 3: Stuck switching valve or failed check valve
Common general cause- Why it ranks here
- Rick's lists a stuck diverter valve (carbon in a hot, corrosive spot) and a failed check valve that lets exhaust back toward the pump.
- What would change this
- Rises if the pump runs but no air reaches the exhaust. Falls if the valves move freely.
Cause 4: Carbon-clogged air passages or lines
Possible — needs testing- Why it ranks here
- Rick's says carbon can restrict the passages in the cylinder head, manifold, tubes and valves.
- What would change this
- Rises if the pump and valves work but flow is low. Falls if the passages are clear.
Cause 5: Water in the air pump (some GM cars)
Supported by vehicle data- Why it ranks here
- A GM bulletin summary for 1994-1996 Impala, Caprice and Roadmaster ties water in the air pump and P0410 to a service kit. This is a summary only and the bulletin is not verified as current.
- What would change this
- Rises if the pump is wet or the car is in the bulletin range. Falls on other vehicles.
What to test first
Start at step 1. Each result tells you what it means and where to go next.
Step 1: Start the engine from a true cold start and listen for the air pump running for the first moments.
IfThe pump does not run
It meansCheck power, fuse and relay.
IfThe pump runs
It meansCheck whether air reaches the exhaust.
Step 2: Check the fuse and relay for the air pump and the connector for corrosion.
IfA fuse is blown or the relay is bad
It meansReplace it, then find out why it failed.
Points to: Blown fuse, bad relay or wiring fault to the air pump
IfPower and ground are present but the pump does not run
It meansThe pump has failed.
Step 3: Have a shop confirm that air reaches the exhaust and that the switching and check valves open.
Warning:Exhaust parts and the manifold are very hot after a cold start; this test is done by a shop.
IfNo air reaches the exhaust
It meansA valve or line is blocked or stuck.
IfFlow is low but valves move
It meansPassages may be clogged.
Symptoms
- Check engine light, often the only sign
- Loud whine or noise from the air pump at start-up
- Hesitation or hard starting Gets more serious: stop and have it checked.
How to fix
Step 1: With the engine off, check the air pump fuse in the fuse box.
Parts and cost context
- Secondary air pump:Test before replacing: several faults give the same code. Labour varies; get a quote.
Labor varies by vehicle and shop; get a quote before you approve a repair.
Compare used part prices on PartPriceGuideOn your vehicle
ChevroletYour car
1994–1996 · Impala
Supported by vehicle dataA GM bulletin summary ties water in the air pump and P0410 to a service kit. Only the one-line cached summary was read, and whether it is still current is not verified.
776513Status unverified
Water in air pump and/or P0410, air pump service kit
1994–1996impala, caprice · NHTSA 52106
Install an air pump service kit when water is in the pump or P0410 is stored.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.
Related codes
No curated relationships for P0410 yet.
P0410 questions
Why does P0410 only show up some mornings?
The system runs only on a cold start, so faults show up when the engine is cold and may not appear on a warm engine.
Sources and review
- P0410 Code: Meaning, Causes and How to Fix It
- P0410 Code Explained: Causes, Diagnosis and Repair
- GM bulletin 776513: water in air pump and/or DTC P0410 (install air pump service kit)
- Last reviewed
- Written by
- Saurabh K.
- Editorial review
- Pending
- Technician review
- Technician review pending
This page explains what a code usually means; it is not a substitute for a professional inspection. How we source and review · Report an error