P0258 Fault Code

Injection Pump Fuel Metering Control B Low (Cam/Rotor/Injector)

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0258 fault code indicates an issue with the fuel injection pump. Specifically, it signals that the fuel metering control B circuit is indicating a low voltage condition. This can be caused by a variety of factors, including a malfunctioning injector, a damaged camshaft, or a faulty rotor.

To diagnose and repair the issue, a comprehensive inspection of the fuel injection system will need to be performed. This may include checking the wiring and connections associated with the fuel metering control circuit, inspecting the fuel pump and its components, and testing the fuel pressure and delivery rate.

If a specific component is found to be at fault, it will need to be replaced or repaired as necessary. In some cases, the entire fuel system may need to be replaced to resolve the issue.

If left unaddressed, the P0258 fault code can lead to a variety of engine performance issues, including reduced fuel efficiency, rough running, and even engine stalling or failure.

What are the symptoms of the P0258 code?

Here are some symptoms that may indicate a P0258 fault code on cars:

• Check Engine Light (CEL) is on
• Rough idling or stalling
• Poor acceleration
• Engine misfire
• Reduced fuel efficiency
• Smoke emission from exhaust

Note that these symptoms may vary depending on the make and model of the car. It is always recommended to consult with a professional mechanic to diagnose and fix the issue correctly.

What causes the P0258 code?

P0258 is a fault code that typically indicates an issue with the fuel metering control circuitry in the injection pump. This fault code is usually caused by one of the following:

1. Failed injection pump: If the injection pump fails, it can cause the fuel metering control circuit to malfunction, leading to the P0258 code.

2. Wiring issues: A faulty wiring harness or damaged wiring can also cause the control circuit to malfunction and trigger the P0258 code.

3. Failed camshaft position sensor: A failed camshaft position sensor can cause inaccurate fuel metering, leading to the P0258 code.

4. Failed fuel injectors: Failed fuel injectors can limit fuel delivery to the engine, causing the fuel metering control circuit to malfunction and triggering the P0258 code.

5. Vacuum leaks: Vacuum leaks in the fuel system can cause the engine to receive inconsistent amounts of fuel, which can lead to the P0258 code.

It is important to note that the specific cause of the P0258 fault code may vary depending on the make and model of the vehicle, so it is always best to consult the vehicle's owner's manual or take the vehicle to a qualified mechanic for diagnosis and repair.

How to fix P0258?

The P0258 fault code refers to an issue with the fuel metering control of the injection pump. This can be caused by a variety of factors including a faulty injector, a malfunctioning cam or rotor, or a problem with the wiring or connectors.

Here are some steps that can help fix the P0258 fault code:

1. Check the connections: Start by checking all the wiring and connectors related to the fuel metering control system. Ensure that all the connections are clean, tight, and free of any corrosion.

2. Check the injector: A faulty injector can cause the fuel metering control system to malfunction. To check the injector, you can use an injector tester to measure its resistance and flow rate.

3. Check the cam and rotor: The cam and rotor are critical components of the fuel metering control system. If these parts are worn out or damaged, they can cause the injection pump to malfunction. Use a dial indicator to measure the cam and rotor runout and ensure that they are within the manufacturer's specifications.

4. Test the injection pump: If all the other components are working fine, then the problem could be with the injection pump itself. You can test the injection pump by following the manufacturer's testing procedure.

5. Replace any faulty parts: If any of the components are found to be faulty, then replace them with new ones to ensure the proper functioning of the fuel metering control system.

It's recommended to take your car to a certified mechanic to diagnose and fix the P0258 fault code to avoid any potential damage to the vehicle.