P012B Diagnostic Trouble Code

P012B is a kind of OBD-II Diagnostic P-Powertrain 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 P012B diagnostic trouble code may include:

Poor fuel economy
Possible spark knock (detonation / pre-ignition)
Misfire
Reduction in engine performance, especially at low RPM levels

Possible Causes :

Dirty air cleaner element Damaged DPF
A plugged converter will cause of host of driveability problems as well as set this code. A severely plugged converter will result in the inability to increase rpm when under load. Look for a code such as P0421 -- catalytic converter efficiency below threshold if the converter indicating a faulty converter.
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 :

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. Now, clear the codes and test-drive the vehicle to see if the code is reset. 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.

Process Tips

Diagnostic trouble code P012B 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 P012B.

Fortunately, P012B is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

P012B Trouble Code For Specific Cars

P012B Rene-bonnet Missile HO2S Heater Resistance (Bank 2 Sensor 3)
P012B Ferrari 308 Insufficient Coolant Temperature for Stable Operation
P012B Porsche 962 Fuel Level Sensor B Intermittent/Bypass Line Monitor
P012B Mg Ya Ambient Air Temperature Sensor Circuit Intermittent
P012B Dort Roadster Ignition Tamper Circuit Short To Battery
P012B Rover 400 Ignition Coil A Secondary Circuit Malfunction
P012B Mercedes S 560 Air Assisted Injector Control Range/Performance