P0300: Random/Multiple Cylinder Misfire Detected
What this check-engine code means in plain English, what usually causes it, and what a fix typically costs.
What P0300 means
The engine control module has detected misfires occurring randomly across multiple cylinders, rather than in one specific cylinder. This means the air-fuel mixture in one or more cylinders is not igniting properly, causing rough running, power loss, and potentially damaging the catalytic converter with unburned fuel.
What causes P0300?
Is P0300 safe to drive?
You can drive short distances to a repair shop, but prolonged driving with misfires can overheat and permanently damage the catalytic converter (a very expensive repair). The vehicle may also stall unexpectedly or lack power for safe merging and passing.
P0300 repair cost
Industry-average estimates. Cost depends heavily on the root cause, from simple spark plug replacement to ignition coils, fuel system repairs, or vacuum leak diagnosis.
Which one is it for your car?
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