What are the common causes of P0300?

Worn or fouled spark plugs. Failed ignition coils or spark plug wires. Vacuum leaks in the intake system. Low fuel pressure or clogged fuel injectors. Mechanical compression issues or a weak fuel pump.

Read freeze frame data and live misfire counters with an OBD-II scanner. Inspect spark plugs, wires, and ignition coils. Smoke test the intake for vacuum leaks. Check fuel pressure and injector performance. Perform a compression test if misfires persist around the same cylinders.

P0300

Random/Multiple Cylinder Misfire Detected

System: Ignition and misfire (P code)
Lamp: Check Engine Light
Category: Powertrain - Ignition

What it means

P0300 means Random/Multiple Cylinder Misfire Detected.

Check these first

Worn or fouled spark plugs
Failed ignition coils or spark plug wires
Vacuum leaks in the intake system
Low fuel pressure or clogged fuel injectors
Mechanical compression issues or a weak fuel pump

What to do next

Read freeze frame data and live misfire counters with an OBD-II scanner
Inspect spark plugs, wires, and ignition coils
Smoke test the intake for vacuum leaks
Check fuel pressure and injector performance
Perform a compression test if misfires persist around the same cylinders

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Updated

Generic SAE J2012 definition. Last updated 2026-08-30.