P0302 on the 2017 Mazda CX-9
The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.
Nobody has written a description of this code yet.
| 01-001-23a | 2023-03-03. Service bulletin. Some customers may complain about a poor acceleration and rough idling or the CHECK ENGINE light ON with DTC P0301:00, P0302:00, P0303:00, P0304:00.NOTE: Only turbo engines are applicable; non-turbo engines are NOT applicable. In most cases, DTCs P030X stores, but sometimes not. Sometimes the CHECK ENGINE light does not recognize this engine concern. This is caused by the variable valve in the exhaust manifold seizing and causing the exhaust port to become hot and the exhaust valve seat to wear unevenly, resulting in compression leakage. To eliminate this concern, the design of the exhaust manifold has been modified. |
|---|---|
| 01-010-18-3442b | 2018-08-20. Service bulletin. Some vehicles may exhibit an engine misfire during acceleration with the check engine light flashing and the following DTC(s). P0302:00 - Cylinder No.2 misfire detected and/or P0303:00 - Cylinder No.3 misfire detected NOTE: Even if a misfire occurred, the DTCs may not be stored because they are set after the continuous misfire occurred for 2 drive cycles. In this case, check if the following information is available to verify if the vehicle is applicable to this Service Information. The customer states that the misfire occurred and at the same time the check engine light started flashing. DTC U0401:00 ((ABS) Signal error from PCM) is detected.This concern may be caused if the exhaust manifold variable valve shaft (1) is out of alignment and/or the exhaust manifold variable valve housing (2) is out of shape. The exhaust manifold variable valve (3) then interferes with the housing and becomes stuck closed when the engine is hot. To eliminate this concern in the future, the production processes and controls have been improved. |
| 01-010-18-3442a | 2018-05-14. Service bulletin. Some vehicles may exhibit an engine misfire during acceleration with the check engine light flashing and the following DTC(s). P0302:00 - Cylinder No.2 misfire detected and/or P0303:00 - Cylinder No.3 misfire detected NOTE: Even if a misfire occurred, the DTCs may not be stored because they are set after the continuous misfire occurred for 2 drive cycles. In this case, check if the following information is available to verify if the vehicle is applicable to this Service Information. The customer states that the misfire occurred and at the same time the check engine light started flashing. DTC U0401:00 ((ABS) Signal error from PCM) is detected. This concern may be caused if the exhaust manifold variable valve shaft (1) is out of alignment and/or the exhaust manifold variable valve housing (2) is out of shape. The exhaust manifold variable valve (3) then interferes with the housing and becomes stuck closed when the engine is hot. To eliminate this concern in the future, the production processes and controls have been improved. |
3 on file from NHTSA, as of 2026-10-19. See them in the bulletin list. A bulletin lists model years: read the document for which vehicles it concerns.