What causes a P2442 code?

P2442 can be triggered by several issues — see the verified probable causes and step-by-step diagnostics shared by mechanics and owners on OBDIY.

Can I drive with a P2442 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with P2442 active.

Follow the step-by-step diagnostic on this page, then read the verified fixes contributed by other Heavy Truck owners — the answer marked "Verified Cause" worked for the original poster.

OBD-II

P2442

P2442 Secondary Air Injection System Switching Valve Stuck Open Bank 1

What it means

Indicates that the secondary air injection (SAI) switching valve is stuck in the open position, allowing unauthorized air flow into the exhaust stream. In heavy-duty diesels, this often relates to specialized emissions control components or air-assisted aftertreatment systems.