B278A Diagnostic Trouble Code

B278A 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 B278A diagnostic trouble code may include:

Poor fuel economy
Possible spark knock (detonation / pre-ignition)
Misfire
The light may stay on or light intermittently as the DPF regenerates. The engine will be sluggish on acceleration.

Possible Causes :

Low fuel pressure caused by a clogged filter, failing fuel pump, failed fuel pressure regulator or clogged or leaking injectors.
Low fuel pressure caused by a clogged filter, failing fuel pump, failed fuel pressure regulator or clogged or leaking injectors.
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 :

Look for damage to the tank indicating impact that may have damaged the fuel pump or sender. 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. It should be pretty close to battery voltage (12 volts). If not, then this is the circuit that has the problem.

Process Tips

Diagnostic trouble code B278A 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 B278A.

Fortunately, B278A is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

B278A Trouble Code For Specific Cars

B278A Allard M Air Bag Driver Circuit Short To Battery
B278A Citroen C4 Ii Fuel Composition Sensor Circuit High Input
B278A Infiniti Fx45
B278A Alfa Romeo Arna Accessory Delay Relay Coil Circuit Failure
B278A Ford Fairmont
B278A Noble M10 Cylinder 1 Misfire Detected
B278A Panhard Et Levassor Panhard Et Levassor Driver Power Window Motor Circuit Short To Ground