U2637 Bentley 3.5-litre Diagnostic Trouble Code

U2637 Bentley 3.5-litre code definition:
U2637 is a kind of OBD-II Diagnostic U-Network Diagnostic Trouble Code for Bentley 3.5-litre.

U2637 Bentley 3.5-litre is defined as Camshaft Position Sensor A Circuit Low. This means the CMP (camshaft position) sensor circuit on engine bank 1 sends an irregular reading. 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 U2637 Bentley 3.5-litre diagnostic trouble code may include:

Reduction in engine performance, especially at low RPM levels
Vacuum leak on the engine
Diminished fuel efficiency
Rich or lean exhaust

Possible Causes :

The Mass Airflow sensor will also cause this problem. Mass Airflow circuit malfunction.
Fuel with a large percentage of sulfur will clog the DPF quickly
Dirty air cleaner element Damaged DPF

Common Misdiagnoses

IC Circuit High Voltage Problem
Control Module Throttle Actuator Position Performance Problem
Air Conditioning (A/C) Clutch Feedback Circuit High Voltage Problem
Cruise Vehicle Speed/Set Speed Difference Too High Problem
PCM Stack Overrun Problem

Repair Processes :

Find out what kind of system you have and verify that voltage to the fuel level sensor is present at the fuel pump wiring harness. 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.

Process Tips

Diagnostic trouble code U2637 Bentley 3.5-litre 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 U2637 Bentley 3.5-litre.

Fortunately, U2637 Bentley 3.5-litre is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.