B2021 Diagnostic Trouble Code

B2021 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 B2021 diagnostic trouble code may include:

Poor fuel economy
Possible spark knock (detonation / pre-ignition)
Misfire
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
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 :

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. Look at the plug wires to make sure they are not burnt or laying on the exhaust. Now, clear the codes and test-drive the vehicle to see if the code is reset.

Process Tips

Diagnostic trouble code B2021 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 B2021.

Fortunately, B2021 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

B2021 Trouble Code For Specific Cars

B2021 Mazda Grand TSS Circuit Intermittent Malfunction
B2021 Honda Acura Integra Pressure Control Solenoid B Control Circuit Range/Performance
B2021 Warszawa 223
B2021 Daewoo Vada Gear Control Malfunction
B2021 Plymouth Road Runner Evaporative Vac Solenoid Circuit Malfunction
B2021 Mercedes Gla Accelerometer Rear Circuit Short To Battery
B2021 Bugatti Type 43 Cylinder 11 Contribution/balance Fault