P2431 Secondary air system pressure or flow sensor reading out of range (bank 1)

Secondary air injection air flow/pressure sensor circuit range/performance

P2431 in short

P2431 means the computer sees the secondary air injection pressure or flow sensor reading outside its expected range on bank 1. Common causes are a failing air pump or its relay, a leaking hose or sensor, or on some GM models a software fault. Have it inspected soon, and avoid long trips.

A secondary air pump blows fresh air into the exhaust for about a minute after a cold start to burn off unburned fuel. A pressure or flow sensor tells the computer whether the air is really moving, and P2431 sets when that reading is out of its expected range.

Volkswagen has a bulletin that lists P2431, P2432 and P2433 together on 2005-2012 models, and owners of 2009-2010 Jettas report the fix as an updated hose and sensor. On the GM side there are bulletins for ECM replacement or software on 2006 Cobalt, HHR and Ion, and for MAP sensor circuit wiring on Colorado, Canyon and H3.

A worn pump or burnt relay connector, as on a 2007 Trailblazer, is the other repeat finding.

Most likely causes

  1. Secondary air pressure sensor or its hose

    Supported by vehicle data
    Why it ranks here
    Two Jetta owners report P2431 with a sensor or hose repair, and Volkswagen has bulletin 261403 for the secondary air codes on 2005-2012 models. KBB lists the sensor among the causes.
    What would change this
    Rises if the hose is cracked or the sensor reading does not change when the pump runs. Falls if both check out.
    How to test the vacuum hoses and intake leaks

  2. Air pump failing or its relay or connector damaged

    Supported by vehicle data
    Why it ranks here
    A 2007 Trailblazer owner reports a melted pump relay connector and a worn pump for P2431, and KBB lists the pump first.
    What would change this
    Rises if the pump does not run or draw normal current on a cold start. Falls if it runs and flows.
    How to test the secondary air pump

  3. One-way check valve or air control solenoid

    Common general cause
    Why it ranks here
    KBB lists the check valve and air control solenoid as general causes of the same pressure-circuit fault.
    What would change this
    Rises if air does not reach the exhaust or the valve is stuck. Falls if both work.

  4. Engine computer replacement or software (some GM models)

    Supported by vehicle data
    Why it ranks here
    GM bulletin 3628 covers P2431 set after ECM replacement on 2006 Ion and Cobalt, and bulletin 050604073 reprograms the ECM for P2431 among other codes on the L61 engine.
    What would change this
    Rises if the code appeared after an ECM replacement or on a covered L61. Falls otherwise.
    How to test the engine control module (ecm / pcm)

  5. MAP sensor circuit wiring broken inside the insulation (GM Colorado, Canyon, H3)

    Possible — needs testing
    Why it ranks here
    GM PIP4409 lists P2431 among the codes set by broken MAP sensor circuit wires on 2004-2012 Colorado and Canyon and 2006-2010 H3. It is one bulletin, so it ranks lower.
    What would change this
    Rises if the wiring is damaged near the sensor. Falls if the circuit tests normal.

What to test first

Start at step 1. Each result tells you what it means and where to go next.

  1. Read all stored codes. Note whether P2432, P2433, P0411 or P0418 are stored with P2431.

    Low riskTool: OBD-II scan tool

    • IfP2432 or P2433 stored too on a Volkswagen

      It meansBulletin 261403 groups them.

      Go to step 2

    • IfP2431 alone

      It meansAsk about bulletins and inspect the hose.

      Go to step 2

  2. Ask a dealer whether your VIN has a secondary air, ECM or MAP wiring bulletin for P2431.

    Low risk

  3. Look at the secondary air pump, its relay and connector, and the hoses to the pressure sensor for melting, cracks or loose fittings.

    Use caution

    Warning:Do not touch the pump or relay with the engine running; they may be hot.

  4. Run the secondary air pump with a bidirectional scan tool and watch the pressure sensor reading.

    Best left to a shopTool: bidirectional scan tool

    Warning:The pump and exhaust parts can be hot. Leave this to a shop.

Symptoms

  • Check engine light
  • Whirring or buzzing noise after a cold start
  • Rough idle or stalling after a cold start Gets more serious: stop and have it checked.
  • Hard cold start or poor acceleration Gets more serious: stop and have it checked.

Compare with: Rough idle with the check engine light on

How to fix

  1. Ask a dealer whether your VIN has an open secondary air, ECM or MAP wiring bulletin for P2431.

Parts and cost context

  • Secondary air pump:The pump is the costly part; confirm it is at fault before buying and rule out hoses and the relay first. Labour varies; get a quote.

Labor varies by vehicle and shop; get a quote before you approve a repair.

Compare used part prices on PartPriceGuide

On your vehicle

Volkswagen

  • 2005–2012 · Jetta

    Supported by vehicle data

    Volkswagen bulletin 261403 covers secondary air codes P2431, P2432 and P2433 on Jetta and other 2005-2012 models; two owners report a hose and sensor repair.

  • 261403Status unverified

    MIL on, secondary air DTCs P2431, P2432, P2433 stored

    2005–2012jetta, beetle, golf, passat · NHTSA 10239827

    Secondary air codes stored in the ECM fault memory on 2005-2012 models.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Chevrolet

  • 2006 · Cobalt

    Supported by vehicle data

    GM bulletin 3628 covers P2431 after an ECM replacement; check the ECM part number.

  • 2007 · Trailblazer

    Supported by vehicle data

    One owner reports P2431 with a melted air pump relay connector and a worn pump. Complaint signal only.

  • 3628 (chevrolet)Status unverified

    P2431 after ECM replacement

    2006cobalt · NHTSA 10018543

    Inspect the ECM part number.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • PIP4409F (chevrolet)Status unverified

    Rough running with P0106, P0107, P0171, P0300, P0502, P1107, P2431

    2004–2012colorado · NHTSA 10154614

    Inspect the MAP sensor circuit wiring for breaks inside the insulation.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • P2432Secondary air pressure sensor signal too low (bank 1)

    Same system Supported by vehicle data

    P2432 is the low-circuit code for the same secondary air pressure sensor. Volkswagen bulletin 261403 lists P2431, P2432 and P2433 together.

  • P2433Secondary air system pressure or flow sensor circuit reading too high (bank 1)

    Same system Supported by vehicle data

    P2433 is the high-circuit code for the same sensor circuit.

  • P0411Secondary air injection flow not as expected

    Same system Possible — needs testing

    P0411 is the secondary air injection system incorrect flow code, which can appear when the pump or its valves are failing.

All Secondary air injection codes

P2431 questions

Is P2431 the same as P2432 or P2433?

They are three codes for the same secondary air pressure sensor circuit: range or performance, low, and high. Volkswagen lists all three in one bulletin.

Can I drive with P2431?

Kelley Blue Book calls it serious and advises against driving, and symptoms can include rough idle or stalling. Have it inspected soon.

Sources and review

  1. P2431 code: secondary air injection system air flow/pressure sensor circuit range/performance bank 1 — Kelley Blue Book (KBB Service Advisor)
  2. NHTSA complaint ODI 1001741: 2007 Chevrolet Trailblazer, P2431 — NHTSA Office of Defects Investigation (owner complaint)
  3. NHTSA complaint ODI 876748: 2010 Volkswagen Jetta, P2431 and P2433 — NHTSA Office of Defects Investigation (owner complaint)
  4. NHTSA complaint ODI 1184675: 2009 Volkswagen Jetta, P2431 and P2432 — NHTSA Office of Defects Investigation (owner complaint)
  5. MIL on, secondary air DTCs P2431, P2432, P2433 stored in ECM fault memory (Volkswagen bulletin 261403) — Volkswagen of America / NHTSA
  6. GM bulletin 3628: P2431 after ECM replacement, inspect ECM part number — General Motors / NHTSA
  7. GM PIP4409F: manifold absolute pressure sensor circuit wiring (P0106, P0107, P0171, P0300, P0502, P1107, P2431) — General Motors / NHTSA
Last reviewed
Written by
Saurabh K.
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