Trouble code · Powertrain · Generic (all makes)

P0300 Random/Multiple Cylinder Misfire Detected

The engine computer has detected misfires that aren't limited to one cylinder.

Safe to drive?
Get it checked now
Limit driving until it's diagnosed
Scanner you need
Any OBD2 scanner
Even a basic code reader shows it
NHTSA complaints quoting it
287
Vehicle complaints, 2015–2025

Common causes

  • Worn spark plugs
  • Failing ignition coils or plug wires
  • Vacuum leak
  • Low fuel pressure or clogged injectors
  • Low compression
  • Bad fuel

Symptoms

  • Rough idle, shaking, hesitation, loss of power
  • The check engine light may flash

Can I drive with it?

If the check engine light is flashing, reduce speed and get it checked right away – a misfire that bad can overheat and destroy the catalytic converter.

Tip: Random misfires across several cylinders point to something they share – fuel pressure, a vacuum leak or old plugs – more than a single bad coil.

Which scanner reads it?

Any OBD2 scanner reads it. Live misfire counts per cylinder (on better tools) help find which cylinders are affected.

Budget tools like the ANCEL AD310 read it; tools with live data and graphing – like the BlueDriver or OBDLink MX+ – help you find the cause. Not sure which fits you? Try the Find My Scanner quiz.

In the data

How common is it? At New York’s emissions inspections in 2020–21, P0300 was the #4 code found on cars that failed – 4.0% of all the codes found.

Of the vehicle complaints owners filed with NHTSA from 2015 to 2025, 287 quote P0300 – most often from Ford, Chevrolet, Honda owners. Complaints lean toward serious problems, so treat this as a sign of how often the code turns up in real reports, not how often cars get it.

Both sources are compared on the Trends page.

General information to help you understand a code – not a diagnosis. Your car’s service information or a qualified mechanic has the final word. See how we research.