P1428 – OBD-II DTC

OBD-II DTC P1428 – EGI Functionality Test Failed

DTC P1428 meaning

DTC P1428 refers to a diagnostic trouble code indicating that the Engine Control Module (ECM) has detected a failure in the EGI (Electronic Gasoline Injection) functionality test. This code is specific to the fuel injection system and suggests that the ECM is unable to properly control the fuel injection process, which can lead to performance issues and increased emissions.

DTC P1428 symptoms

Common symptoms associated with DTC P1428 may include:

• Check Engine Light illuminated
• Decreased engine performance
• Rough idling or stalling
• Increased fuel consumption
• Difficulty starting the engine

DTC P1428 causes

Several factors can contribute to the occurrence of DTC P1428, including:

• Faulty fuel injectors
• Defective ECM
• Wiring issues or poor connections in the fuel injection system
• Vacuum leaks affecting air-fuel mixture
• Clogged fuel filter or fuel lines

DTC P1428 seriousness

DTC P1428 is considered a serious issue as it can lead to significant engine performance problems and increased emissions. If left unaddressed, it may result in further damage to the engine or fuel system components, potentially leading to costly repairs.

How to diagnose DTC P1428

To diagnose DTC P1428, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the P1428 code.
2. Check for any additional trouble codes that may provide more context.
3. Inspect the fuel injectors for proper operation and any signs of damage.
4. Examine the wiring and connectors related to the fuel injection system for any faults.
5. Test the fuel pressure to ensure it meets manufacturer specifications.
6. Check for vacuum leaks that could affect the air-fuel mixture.
7. Perform a visual inspection of the ECM and its connections.

How to fix DTC P1428 step-by-step instructions

To fix DTC P1428, follow these step-by-step instructions:

1. Address any identified wiring issues or poor connections.
2. Replace faulty fuel injectors if they are not functioning correctly.
3. Repair or replace the ECM if it is determined to be defective.
4. Replace the fuel filter if it is clogged or restricted.
5. Fix any vacuum leaks found during the diagnosis.
6. Clear the DTC using an OBD-II scanner and test drive the vehicle to ensure the issue is resolved.

How to erase DTC P1428

To erase DTC P1428, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the ignition without starting the engine.
3. Navigate to the option to clear or erase trouble codes on the scanner.
4. Confirm the action to erase the DTC.
5. Disconnect the scanner and start the engine to verify that the code does not reappear.

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