B0021 Plymouth Acclaim OBD Code

OBD/2 B0021 error code description and symptoms.

Catalytic converters must be warm before they can work properly. On a cold start the PCM provides a rich mixture to keep the cold engine running.
All that extra fuel goes into the catalytic converter. But the exhaust isn't very hot, because, ah, the engine is pretty cold. GM has employed several strategies to fire up the catalytic converter quicker and reduce cold start emissions. One way is to use a secondary air pump that pumps outside air directly into the catalytic converter.

One example of this would be when an automatic vehicle in placed in gear. To prevent the added drag from the torque converter and transmission from reducing the idling speed, the PCM will command the idle control valve to allow more air to enter the engine, while at the same time, adjusting the injector pulse width to inject more fuel to suit the increased amount of air. Note that the idle air control valve is closed by the PCM when the throttle plate is opened to prevent excess air from entering the engine.

B0021 Plymouth Acclaim Error Code Repair Process :

If your throttle position sensor/switch a circuit range/performance problem check engine light is illuminated, it's best to take it in for diagnostic testing, which can feel like a hassle. Because while the lights vary in appearance from vehicle to vehicle, all have the same basic meaning: There's a problem with the car's emissions system. The on-board diagnostics system B0021 and engine control unit are in charge of monitoring a bunch of different throttle position sensor/switch a circuit range/performance problem, and if they get a reading that's a little out of whack, up pops the check engine light.

Common Causes of Plymouth Acclaim B0021 OBD2 Code

A common cause of code B0021 is the failure of Throttle Position Sensor/Switch A Circuit Range/Performance Problem, but there are several other possible causes as well, such as ;

Dirty Oil
Damaged ECM
Fuel injector leaks
Open or short in the CMP sensor circuits

B0021 is a kind of Body Trouble Code

Auto body problems aren't always easy to spot. Diagnosing auto body problems sometimes requires a little know-how. In this section you'll find articles dedicated to teaching you how to diagnose auto body problems.

Engine OBD 2 Codes website is a freeware resource center for engine trouble codes.

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B0021 Plymouth Acclaim OBD Code

B0021 Plymouth Acclaim Error Code Repair Process :

Common Causes of Plymouth Acclaim B0021 OBD2 Code

B0021 code for other Plymouth cars