B2908 Diagnostic Trouble Code

B2908 is a kind of OBD-II Diagnostic B-Body Diagnostic Trouble Code.

It is considered generic because it applies to all makes and models of vehicles, although specific repair steps may be different depending on your car model.

Symptoms

Symptoms of a B2908 diagnostic trouble code may include:

Faulty or damaged wiring
The engine oil will exhibit dilution from the ECUs attempts to increase engine temperature. Some vehicles advance the fuel injection timing slightly after top center to afterburn a small amount of fuel to increase exhaust temperatures. Some of this fuel enters the crankcase. When the ECU determines the necessity to regenerate the DPF, the service life of the oil be shortened significantly
Poor fuel economy
Diminished fuel efficiency

Possible Causes :

The Mass Airflow sensor is a hot wire that senses the volume of air entering the intake manifold. The computer uses this information to control fuel mixture.
Defective ECU strategies or components will prevent proper regeneration
A large vacuum leak would cause a massive amount of un-metered air to enter the intake manifold resulting in an overly lean mixture.

Repair Processes :

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. Check to make sure they are not burnt or corroded. If in doubt, get some Electrical Contact cleaner at any parts store if cleaning of the terminals is needed.

Process Tips

Diagnostic trouble code B2908 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 B2908.

Fortunately, B2908 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

B2908 Trouble Code For Specific Cars

B2908 Austin Maestro Autolamp Sensor Input Circuit Short To Battery
B2908 Toyota Isis Oil Level Switch Circuit Short To Battery
B2908 Mercedes E 280 ABS Power Relay Output Short Circuit To Battery
B2908 Toyota Corsa O2 Sensor Circuit No Activity Detected (Bank 2 Sensor 3)
B2908 Fiat Esv Lamp Seat Belt Circuit Short To Battery
B2908 Toyota Caldina O2 Sensor Circuit Low Voltage (Bank 2 Sensor 1)
B2908 Fairthorpe Electrina Injector Circuit Malfunction - Cylinder 2