P0300 on Mazda vehicles Misfire detected, but not isolated to one cylinder

A model year is listed because the code is named in its own record — a bulletin filed against it, or an owner’s complaint about it — not because every one of these vehicles sets it. Counts are documents in NHTSA’s files, not failure rates.

Bulletins and campaigns Mazda filed with NHTSA whose summary names P0300. Quote the document number at the service desk — it is a diagnosis the maker has already written down.

• 01-014-16-3208A Service bulletin
  2016-07-29 · Engine
• SOME VEHICLES MAY EXPERIENCE A LACK OF ENGINE POWER/ROUGH IDLING AND THE CHECK ENGINE LIGHT ON WITH ONE OR MORE OF THE MISFIRE RELATED DTCS OF P0300:00, P0301:00, P0302:00, P0303:00 AND P0304:00. THIS CONCERN MAY BE CAUSED BY AN INTERNAL FAILURE OF THE IGNITION COIL(S) DUE TO A HIGH DIFFERENCE BETWEEN COLD AND WARM AMBIENT TEMPERATURES. THE PRODUCTION METHOD OF THE IGNITION COIL HAS BEEN CHANGED T
• 01-014-16-3208A Service bulletin
  2016-07-29 · Engine
• SOME VEHICLES MAY EXPERIENCE A LACK OF ENGINE POWER/ROUGH IDLING AND THE CHECK ENGINE LIGHT ON WITH ONE OR MORE OF THE MISFIRE RELATED DTCS OF P0300:00, P0301:00, P0302:00, P0303:00 AND P0304:00. THIS CONCERN MAY BE CAUSED BY AN INTERNAL FAILURE OF THE IGNITION COIL(S) DUE TO A HIGH DIFFERENCE BETWEEN COLD AND WARM AMBIENT TEMPERATURES. THE PRODUCTION METHOD OF THE IGNITION COIL HAS BEEN CHANGED T
• 01-014-16-3208 Service bulletin
  2016-06-10 · Engine
• SOME VEHICLES MAY EXPERIENCE A LACK OF ENGINE POWER/ROUGH IDLING AND THE CHECK ENGINE LIGHT ON WITH ONE OR MORE OF THE MISFIRE RELATED DTCS OF P0300:00, P0301:00, P0302:00, P0303:00 AND P0304:00. THIS CONCERN MAY BE CAUSED BY AN INTERNAL FAILURE OF THE IGNITION COIL(S) DUE TO A HIGH DIFFERENCE BETWEEN COLD AND WARM AMBIENT TEMPERATURES. THE PRODUCTION METHOD OF THE IGNITION COIL HAS BEEN CHANGED T
• 01-011-16-3139A Service bulletin
  2016-06-20 · Engine
• WHEN THE ENGINE IS STARTED FOR THE FIRST TIME AFTER PARKING THE VEHICLE OVERNIGHT IN COLD CONDITIONS (BELOW 32 DEGREES FAHRENHEIT / 0 DEGREES CELSIUS), SOME VEHICLES MAY EXHIBIT A ROUGH IDLE AND/OR THE CHECK ENGINE LIGHT ON WITH ANY OF THE FOLLOWING DTC(S) STORED IN MEMORY.•P0300 - RANDOM MISFIRE DETECTED•P0301 - CYLINDER NO.1 MISFIRE DETECTED•P0302 - CYLINDER NO.2 MISFIRE DETECTED •P0303 - CYLIND
• 01-002-17-3299a Service bulletin
  2017-03-02 · Engine And Engine Cooling — Exhaust System
• When the engine is started for the first time after parking the vehicle overnight in cold conditions (below 32 degrees Fahrenheit / 0 degrees Celsius), some vehicles may exhibit a rough idle and/or the check engine light on with any of the following DTC(s) stored in memory.?P0300 - Random misfire detected ?P0301 - Cylinder No.1 misfire detected ?P0302 - Cylinder No.2 misfire detected ?P0303 - Cyli
• 01-006-18-3429 Service bulletin
  2018-03-09 · Engine And Engine Cooling — Exhaust System
• When the engine is started for the first time after parking the vehicle overnight in cold conditions (below 32 degrees Fahrenheit / 0 degrees Celsius), some vehicles may exhibit a rough idle and/or the check engine light on with any of the following DTC(s) stored in memory. P0300 - Random misfire detected P0301 - Cylinder No.1 misfire detected P0302 - Cylinder No.2 misfire detected P0303 - Cylinde
• 01-007-19-3541 Service bulletin
  2019-01-24 · Engine
• When the engine is started for the first time after parking the vehicle overnight in cold conditions (below 32 degrees Fahrenheit / 0 degrees Celsius), some vehicles may exhibit a rough idle and/or the check engine light on with any of the following DTC(s) stored in memory. P0300 - Random misfire detected P0301 - Cylinder No. 1 misfire detected P0302 - Cylinder No. 2 misfire detected P0303 - Cylin
• 01-001-21-3761a Service bulletin
  2021-07-26 · Engine And Engine Cooling
• Some vehicles may exhibit an occasional rough idle accompanied with DTC P0300:00 (Random misfire) due to the following: 1. While closing the EGR valve, carbon deposit etc. pinched at the valve seat prevents the valve from closing completely. 2. The closed position of the EGR valve is learned improperly as it is not equipped with a position sensor. 3. While idling, the EGR gas improperly mixes with
• 01-001-21-3761 Service bulletin
  2021-01-14 · Engine And Engine Cooling
• Some vehicles may exhibit an occasional rough idle accompanied with DTC P0300:00 (Random misfire) due to the following: 1. While closing the EGR valve, carbon deposit etc. pinched at the valve seat prevents the valve from closing completely. 2. The closed position of the EGR valve is learned improperly as it is not equipped with a position sensor. 3. While idling, the EGR gas improperly mixes in
• 01-002-24 Service bulletin
  2024-02-12 · Engine And Engine Cooling
• Some customers may experience a check engine light illumination at idle while stopped with DTC P0300:00 stored, resulting in rough idle conditions. • P0300:00: Random misfire detected This concern is caused by improper engine control in the idle range. To eliminate the concern, the PCM control software has been modified.

A stored code names the test that failed, never the part that caused it. The record above is what Mazda and its owners have filed about it; the code’s page across every make has the whole file.