B0138 Volvo 760 Diagnostic Trouble Code

B0138 Volvo 760 code definition:
B0138 is a kind of OBD-II Diagnostic B-Body Diagnostic Trouble Code for Volvo 760.

B0138 Volvo 760 is described as Fuel Rail Pressure Sensor Circuit Malfunction. This code is strictly about the incoming signal from the FRP (fuel rail pressure) sensor falling below the calibrated limit for a certain period of time. The spark should have a light tan color. If the sensor probe comes with white and chalky parts, this means it has been lagging between switching phases, and should be replaced.

Symptoms

Symptoms of a B0138 Volvo 760 diagnostic trouble code may include:
Place of B0138 in engine

Possible Causes :

  • An air leak forward of the DPF will change the sensor readings resulting in the code
  • Rusty exhaust systems, cracked exhaust manifolds or damaged or missing gaskets or donuts will cause air leaks.
  • Faulty IMRC actuator relay (if equipped)

Common Misdiagnoses

  1. Control Module Throttle Actuator Position Performance Problem
  2. Air Conditioning (A/C) Clutch Feedback Circuit High Voltage Problem
  3. Cruise Vehicle Speed/Set Speed Difference Too High Problem
  4. Kick-Down Switch Failed Short Problem
  5. Park/Neutral Postion (PNP) Switch Circuit Engine Torque Signal Circuit Problem

Repair Processes :

If the scan tool has that capability, and the scan tool can operate the IMRC valves, then the problem is either resolved and a simple code clearing is all that's left or a new PCM would be called for. With the valve disconnected, the red voltmeter lead should be attached to the IMRC valve power wire and the black voltmeter lead connected to ground. Oxygen sensors signal the engine management computer the amount of oxygen present in the exhaust, which is used in determining and controlling the fuel ratio.

Process Tips

Diagnostic trouble code B0138 Volvo 760 is not difficult to diagnose and repair. Thus, it always pays to have a qualified technician to look after your vehicle should this error code arise.

Diagnosing this code requires the engine to be in good running shape, without unmetered air entering the engine. If other codes that relates to misfiring condition, lean running or air entering the engine is present, then you must first fix those error codes before B0138 Volvo 760.

Fortunately, B0138 Volvo 760 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

Diagnostic Trouble Code look-up and check engine light code viewer.

About Us | Contact | Privacy

Copyright 2024 - https://DiagnosticTrouble.com

Small Logo