Fault-Code Library · Combustion
P0300: Random / multiple-cylinder misfire
Misfires are occurring across more than one cylinder or without one consistent cylinder pattern.
Common symptoms
- •Shaking idle
- •Flashing warning light
- •Poor acceleration
- •Fuel smell
Likely causes
- •Ignition faults
- •Air or fuel imbalance
- •Injector problems
- •Mechanical compression issue
First checks
- •Stop heavy driving if the warning lamp flashes
- •Read cylinder-specific counters
- •Check plugs, coils, trims, injectors, and compression logically
Important
Active misfire can overheat and damage the catalytic converter.
A fault code identifies a detected condition, not a failed part. Confirm manufacturer-specific subcodes and live data.
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