Ignition / MisfireHigh ImpactPetrol

P0304 — Diagnostic Trouble Code P0304

OBD-II diagnostic code P0304 relates to the ignition / misfire system. This code is logged when the ECU detects a parameter outside its expected operating range.

6+

Affected Brands

12+

ECU Platforms

3

Related Services

8

Related DTCs

Symptoms

What the driver typically experiences when P0304 is stored

!Check Engine Light (may flash)
iEngine misfires
iRough idle
iLoss of power

Why does P0304 appear after tuning?

This code may appear after ECU modifications when the affected system monitoring has not been fully recalibrated for the new operating parameters.

How proper calibration can address P0304

WEREMAP professional calibrations include comprehensive diagnostic management for all affected systems, preventing unnecessary fault codes while maintaining safe operation.

Related Tuning Services

Relevant services for the system behind P0304

Stage 1Stage 2DTC Off

Related Diagnostic Codes

Codes from the same diagnostic system as P0304

P0300High Impact

Random/Multiple Cylinder Misfire Detected

P0302High Impact

Diagnostic Trouble Code P0302

P0301High Impact

Diagnostic Trouble Code P0301

P0303High Impact

Diagnostic Trouble Code P0303

P0306High Impact

Diagnostic Trouble Code P0306

P0017Moderate Impact

Diagnostic Trouble Code P0017

P0014Moderate Impact

Diagnostic Trouble Code P0014

P0366High Impact

Diagnostic Trouble Code P0366

Affected ECU Platforms

Bosch MED17.7.2Bosch MED17.1.9Bosch MED17.1.9 MED17.9.9Bosch MED17.5.21Keihin SH7058Bosch MED17.8.31 MED17.5.4Bosch MED17Bosch MEVD17.2.6 MEVDBosch MED9.6Bosch MEVD17.2.2Siemens/Continental SIMOS10.1xBosch ME9.7

Commonly Affected Vehicles

Land RoverRange RoverBosch MED17.1.9
AudiA3Bosch MED17.5.21
HondaodysseyKeihin SH7058
MBA / A BerlineBosch MED17.7.2
Land RoverRange Rover EvoqueBosch MED17
BMWX5Bosch MEVD17.2.6 MEVD
FerrariFFBosch MED9.6
BMW5 Serie - SedanBosch MEVD17.2.2

Based on data from 6+ vehicle brands. P0304 is not limited to these models.

Frequently Asked Questions

What does P0304 mean?â–¼
OBD-II diagnostic code P0304 relates to the ignition / misfire system. This code is logged when the ECU detects a parameter outside its expected operating range.
Why does P0304 appear after ECU tuning?â–¼
This code may appear after ECU modifications when the affected system monitoring has not been fully recalibrated for the new operating parameters.
How do you prevent P0304 during remapping?â–¼
WEREMAP professional calibrations include comprehensive diagnostic management for all affected systems, preventing unnecessary fault codes while maintaining safe operation.
Which vehicles are affected by P0304?â–¼
P0304 is commonly found on Land Rover, Audi, Honda, MB, BMW, Ferrari vehicles equipped with Bosch MED17.7.2, Bosch MED17.1.9, Bosch MED17.1.9 MED17.9.9, Bosch MED17.5.21 ECU platforms.
What other codes appear alongside P0304?â–¼
P0304 frequently appears together with P0300, P0302, P0301, P0303, P0306. These related codes typically originate from the same system modification and should be addressed together in the calibration.

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