What causes a SPN 273 code?

SPN 273 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 273 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 273 active.

How do I fix SPN 273?

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 273

J1939 SPN 273 — Fuel/Air parameter

What it means

SPN 273 is a generic parameter for the Fuel/Air system. It indicates that the relationship between the fuel delivered and the air intake is outside of the expected calibrated range, but the ECM hasn't isolated it to a specific sensor yet.