P2443: AIR valve stuck-closed code within a pressure-flow check

The standardized P2443 label identifies a secondary-air switching valve stuck closed on Bank 2. The cited GM Group 06 table includes P2443 as “valve stuck closed” within a shared secondary-air flow verification row. It does not separately establish Bank 2 location or provide a code-specific valve-position sensor test.

The source measures system behavior

During normal commanded AIR operation, this monitor compares modeled and measured pressure. The shared row gives a pressure ratio above 1.4 for flow restriction and below 0.8 for leakage such as a disconnected exhaust-manifold pipe. These are contrasting system-level outcomes, not two interchangeable reasons to replace a valve.

The table groups P0411, P2443 and P2444 together. It does not publish the complete selection logic that assigns each outcome to an individual code. Consequently, the numerical ratios should not be presented as an isolated P2443 bench-test specification.

Capture the active AIR event

The listed test needs AIR active, an operating engine, airflow between 1 and 20 g/s and more than eight seconds since engine start. It evaluates a 15-second interval once per driving cycle. Pressure, airflow, intake temperature, coolant, speed and relay faults are among the prerequisites that can prevent a valid result.

This makes an active, qualified pressure comparison more useful than judging the valve from idle behavior after AIR operation has ended. Preserve companion codes and monitor status so a circuit problem is not mistaken for proven mechanical closure. The source supports the monitor explanation but leaves bank mapping and detailed fault isolation unresolved.

Source and applicability

GM 2009 09OBDG06 Engine Diagnostics, shared secondary-air flow verification row across physical pages 24–25. Bank 2 mapping and per-code threshold selection are not resolved by this source.

General Motors source, physical page 24 · General Motors source, physical page 25