2014-2018 Chevrolet Silverado 1500 5.3L: OBD Codes and What to Check First

Codes recorded for this model

• P0300 Random or Multiple Cylinder Misfire Detected Stop driving Shop $120–$900 2 weeks estimate
• P0301 Cylinder 1 Misfire Detected Stop driving Shop $120–$700 2 weeks estimate

What to check first on this engine

These come from how this specific engine fails, not from a generic code list.

1. 1

   Suspect the AFM lifters before the ignition

   Active Fuel Management lifter failures on the 5.3L produce misfire codes that read like ignition problems. A coil swap that changes nothing is the usual clue.

2. 2

   Run a compression test on the misfiring cylinder

   A cylinder that reads well below its neighbors points at a collapsed lifter or a valve problem, and no ignition part will fix it.

3. 3

   Compare misfire counts hot and cold

   AFM lifter faults often show up once the engine is warm and drops into four-cylinder mode. Watch the counters through a full warm-up cycle.