C0373 Alfa Romeo Brera Diagnostic Trouble Code

C0373 Alfa Romeo Brera code definition:
C0373 is a kind of OBD-II Diagnostic C-Chassis Diagnostic Trouble Code for Alfa Romeo Brera.

C0373 Alfa Romeo Brera is described as Oxygen Sensor Circuit No Activity Detected (Bank 1, Sensor 1). This means there's a problem in the front oxygen sensor on Bank 1, as the O2 sensor is inactive. Other symptoms that may indicate this problem are when the Check Engine Light illuminates and when there is a visible lack of engine power.

Symptoms

Symptoms of a C0373 Alfa Romeo Brera diagnostic trouble code may include:

Rich or lean exhaust
Fuel pressure too low
Engine surge
If the DPF is not cleared the ECU will revert to the "Limp Home Mode" until the situation is corrected

Possible Causes :

A large air leak at or near the number one oxygen sensor would also cause a lean mixture.
Faulty IMRC actuator relay (if equipped)
Faulty IMRC actuator/sensor

Common Misdiagnoses

Crankshaft Position Sensor Circuit Performance Problem
TP Sensor Learn Not Complete Problem
Low Coolant Circuit Problem
Cruise Control System - Vehicle Accel Too High Problem
Kick-Down Switch Failed Short Problem

Repair Processes :

It should be pretty close to battery voltage (12 volts). If not, then this is the circuit that has the problem. 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.

Process Tips

Diagnostic trouble code C0373 Alfa Romeo Brera 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 C0373 Alfa Romeo Brera.

Fortunately, C0373 Alfa Romeo Brera is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.