P0492: owner reports and bulletins

Powertrain (generic, all makes). We haven't written the explanation for this code yet. Below is what owners and manufacturers have filed with NHTSA.

Got P0492 on your scanner? Tell the mechanic your year, make, model and any symptoms and you'll get the likely cause and what to check first. Ask about this code.

What owners report to NHTSA

No consumer complaints filed with NHTSA mention P0492. That usually means it's rare, or owners don't quote the code when they file.

Manufacturer service bulletins that name P0492

4 technical service bulletins and manufacturer communications filed with NHTSA mention P0492, from 2 makes. A bulletin means the manufacturer has documented a known cause or a fix procedure for that model. Examples:

  • AUDI A4 (2009, 2010, 2011), bulletin 10210604: DTC P0491 and P0492 (Secondary Air System Insufficient Flow, Bank 1/2) are stored at the same time.
  • ASTON MARTIN DB11 (2017, 2018, 2019), bulletin 10154220: V12 Secondary air injection codes P0492 P0491
  • AUDI Q7 (2011, 2012, 2013, 2014), bulletin 10119937: The MIL is on due to DTCs P0491 and P0492 being stored in the ECM.

Sources: NHTSA Office of Defects Investigation complaint database and manufacturer communications file, snapshots September 2026. A complaint or bulletin that mentions a code is a report about that vehicle, not a statement that the code has one cause.