What causes a SPN 314 code?

SPN 314 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 SPN 314 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 314 active.

How do I fix SPN 314?

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.

OBDIY

J1939 SPN

SPN 314

J1939 SPN 314 — Fuel/Air parameter

What it means

SPN 314 typically indicates an electrical or performance fault related to the Intake Manifold Pressure/Air parameter. It often signifies the data is valid but out of the normal operating range, or there is an intermittent signal interruption.