P128A 2016 GMC Sierra Code - Fuel Rail Pressure Sensor 1 Internal Performance
Quick Answer
The Engine Control Module (ECM) uses the Fuel Rail Pressure (FRP) sensor to constantly adjust the high-pressure fuel pump's feed rate so that the ideal pressure is permanently maintained in the high-pressure section (between the high-pressure fuel pump and the injectors) by means of closed-loop control. Common causes include Low or no fuel, Faulty Fuel Rail Pressure (FRP) Sensor, Fuel Rail Pressure harness is open or shorted. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P128A 2016 GMC Sierra indicates Fuel Rail Pressure Sensor 1 Internal Performance.
- Common causes
- Common causes include Low or no fuel, Faulty Fuel Rail Pressure (FRP) Sensor, Fuel Rail Pressure harness is open or shorted.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P128A 2016 GMC Sierra Description
What are the Possible Causes of the DTC P128A 2016 GMC Sierra?
- Low or no fuel
- Faulty Fuel Rail Pressure (FRP) Sensor
- Fuel Rail Pressure harness is open or shorted
- Fuel Rail Pressure circuit poor electrical connection
- Faulty Fuel Pump
How to Fix the DTC P128A 2016 GMC Sierra?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P128A 2016 GMC Sierra code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
Need more information about the P128A 2016 GMC Sierra code?
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Frequently Asked Questions about P128A 2016 GMC Sierra Code
What does the OBDII code P128A mean on a 2016 GMC Sierra?
Code P128A indicates an issue with the internal performance of Fuel Rail Pressure Sensor 1, which monitors fuel pressure in the high-pressure fuel system.
What are the common symptoms of code P128A in a 2016 GMC Sierra?
Common symptoms include poor engine performance, rough idling, reduced fuel efficiency, difficulty starting, and possible illumination of the Check Engine Light.
What causes P128A to occur on a 2016 GMC Sierra?
The code can be caused by a faulty fuel rail pressure sensor, wiring issues, a malfunctioning fuel pump, or contamination in the fuel system.
How do I diagnose code P128A on my GMC Sierra?
Diagnosis involves using an OBDII scanner to confirm the code, inspecting the wiring and connectors for damage, and testing the fuel rail pressure sensor with a multimeter or scan tool.
Can I drive my 2016 GMC Sierra with code P128A?
Driving with this code is not recommended, as it can lead to poor engine performance and potential long-term damage to the fuel system.
How is code P128A fixed on a 2016 GMC Sierra?
Repairs may include replacing the fuel rail pressure sensor, repairing or replacing damaged wiring, cleaning the fuel system, or addressing issues with the fuel pump.
How much does it cost to fix code P128A on a GMC Sierra?
Repair costs can range from $150 to $500 or more, depending on whether the sensor, wiring, or fuel pump needs replacement.
Can a dirty fuel filter cause P128A on a GMC Sierra?
While not a direct cause, a clogged fuel filter can restrict fuel flow, leading to abnormal pressure readings that may trigger the code.
Does P128A require reprogramming the ECM?
Typically, reprogramming the ECM is not required. Once the issue is fixed, clearing the code and performing a test drive should resolve the problem.
What tools are needed to fix code P128A on a 2016 GMC Sierra?
You'll need an OBDII scanner, multimeter, basic hand tools, and possibly a fuel pressure gauge to diagnose and repair this issue.
Discuss the causes and fixes for P128A 2016 GMC Sierra OBDII Code
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