What causes a SPN 88 code?

SPN 88 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 88 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 88 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.

OBDIY

J1939 SPN

SPN 88

J1939 SPN 88 — Engine parameter

What it means

SPN 88 is the 'Engine Air Filter Differential Pressure' or 'Engine Pressure Ratio'. It indicates that the pressure drop across the intake/exhaust system is outside of the normal operating range.