HomeP0304 · Manufacturer communications

P0304 · Manufacturer communications

Source wording can vary by vehicle and suffix. It is shown as written, not as a universal diagnosis.

P0304 →

B26-003

ACURA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

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B26-002

ACURA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

Read communication ↗

B26-001

ACURA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

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BEBM08262026901

ACURA

Reported code forms P0304

Dealer Message - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire, and/or DTCs P0300 through P0304 stored.

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A26-099

HONDA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

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A26-098

HONDA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

Read communication ↗

A26-097

HONDA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

Read communication ↗

A26-019

HONDA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

Read communication ↗

A26-018

HONDA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

Read communication ↗

A26-017

HONDA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

Read communication ↗

A26-016

HONDA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

Read communication ↗

A26-013

HONDA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

Read communication ↗

A26-012

HONDA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

Read communication ↗

A26-011

HONDA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

Read communication ↗

A26-010

HONDA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

Read communication ↗

A26-009

HONDA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

Read communication ↗

A26-008

HONDA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

Read communication ↗

A26-007

HONDA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

Read communication ↗

A26-006

HONDA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

Read communication ↗

A26-005

HONDA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

Read communication ↗

A26-004

HONDA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

Read communication ↗

A26-003

HONDA

Reported code forms P0304

Service Bulletin - Under certain conditions, the cylinder head gasket effectiveness may be reduced which may cause vehicles to experience overheating, coolant loss, misfire and/or DTCs P0300 thru P0304 stored.

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09-020-26

JEEP

Reported code forms P0304-00

Umbrella Valve Seal Missing From Cylinder Vehicle may exhibit a MIL-ON. SYMPTOM: Upon inspection the technician may find that one or more of the following Diagnostic Trouble Codes (DTCs) have set: ● P0300-00 -…

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JEEP

Reported code forms P0304-00

Umbrella Valve Seal Missing From Cylinder Head Cover Customer may experience a MIL-ON and/or an indication of low engine oil level. SYMPTOM: Upon inspection the technician may find the following: 1. One or more of the…

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09-017-26

JEEP

Reported code forms P0304-00

Umbrella Valve Seal Missing From Cylinder Head Cover Customer may experience a MIL-ON and/or an indication of low engine oil level. SYMPTOM: Upon inspection the technician may find the following: 1. One or more of the…

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18-072-26

RAM

Reported code forms P0304-00

GMET6 SO MIL Changes At Elevation Above 1,000 FT Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes…

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09-013-26

JEEP

Reported code forms P0304-00

Engine Runs Rough Customers may experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle may SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P0300-00 -…

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SSM 54948

FORD, LINCOLN

Reported code forms P0304

Some 2025-2026 Explorer/Aviator/Police Interceptor Utility non-hybrid vehicles built on 06-Feb-2025 and through 13-Dec-2025 may exhibit various drivability symptoms including a rough idle or hesitation shortly after…

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DODGE

Reported code forms P0304

Flash: Powertrain Control Module (PCM) Updates Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician must find one or more of the following Diagnostic…

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JEEP

Reported code forms P0304

Flash: Powertrain Control Module (PCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ●…

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