What causes a SPN 350 code?

SPN 350 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 350 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 350 active.

How do I fix SPN 350?

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 350

J1939 SPN 350 — Fuel/Air parameter

What it means

SPN 350 is a generic J1939 parameter for 'Fuel/Air' ratio or intake-related sensors. It usually triggers when the Engine Control Module (ECM) detects an electrical signal that is outside of the calibrated logical range for air induction or fuel-air mixing calculations.