What causes a P0278 code?

P0278 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 P0278 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with P0278 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

OBD-II

P0278

Cylinder 6 Contribution/Balance

What it means

The Engine Control Module detects that cylinder 6 is performing poorly compared to others, often due to a faulty injector or low compression.