Engine-Codes - Generic - P128F

P128F - Fuel Rail Pressure Sensors 1 and 2 Signals Message Counter Incorrect

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3  What is this?
Table of contents

P128F Possible Causes

  • Faulty Fuel Rail Pressure Sensor
  • Fuel Rail Pressure Sensor harness is open or shorted
  • Fuel Rail Pressure Sensor circuit poor electrical connection

How is the P128F code repair?

Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

What is the cost to diagnose the P128F code

Labor: 1.0

The cost to diagnose the P128F code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.

Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

P128F Meaning

The fuel rail pressure sensor transmits fuel pressure and temperature information by serial data. The fuel rail pressure sensor internal microprocessor allows 4 separate sensor outputs from one 3 wire sensor. The Engine Control Module (ECM) supplies the fuel rail pressure sensor with a 5 V reference circuit, a low reference circuit, and an asynchronous signal/serial data circuit. The asynchronous signal means communication is only going from the fuel rail pressure sensor to the ECM. The ECM decodes the serial data signal into separate voltages which are displayed on a scan tool as the voltage inputs from the Fuel Temperature Sensor, Fuel Rail Pressure Sensor and Fuel Rail Pressure Sensor 2.

More Information

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Information for specific makes

  • P128F BUICK Fuel Rail Pressure Sensors 1 and 2 Signals Message Counter Incorrect
  • P128F CADILLAC Fuel Rail Pressure Sensors 1 and 2 Signals Message Counter Incorrect
  • P128F CHEVROLET Fuel Rail Pressure Sensors 1 and 2 Signals Message Counter Incorrect
  • P128F GMC Fuel Rail Pressure Sensors 1 and 2 Signals Message Counter Incorrect

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