P2921 Trouble Code

View P2921 obd/2 error code description and symptoms. P2921 engine photo

Mass Air Flow (MAF) Sensor Intermittent The MAF sensor circuit is monitored by the PCM for sudden voltage (or air flow) input change through the comprehensive component monitor (CCM). If during the last 40 warm-up cycles in key ON engine running the PCM detects a voltage (or air flow) change beyond the minimum or maximum calibrated limit, a continuous memory diagnostic trouble code (DTC) is stored.

As the engine heats up and combustion becomes easier and more complete, the PCM will command the idling control valve to increase the amount of air entering the engine to suit the changing conditions. However, when the load on the engine changes, say, when some electrical consumers or other systems are either turned on or off, the PCM adapts the signal voltage to the idle control valve to ensure that the idling speed remains stable, and at the RPM specified by the manufacturer.

P2921 Error Code Repair Process :

If your vehicle failed a P2921 test and the P2921 Check Engine Light is NOT on, chances are you have a problem with the OBDII system, a burned out MIL lamp, or a faulty catalytic converter. The converter is essentially an afterburner that cleans up the exhaust after it exits the engine. The OBDII system uses lamp headlamp low-beam circuit open a ownstream oxygen sensor to monitor the efficiency of the converter, and it should detect a drop in converter efficiency if the converter has been contaminated or is failing (ignition misfiring, leaky exhaust valves, and oil burning can all damage the converter). What you want to look lamp headlamp low-beam circuit open: Any conditions that might cause ignition misfire, an overly rich or lean fuel condition, or loss of compression. Use your OBD Express DIY to look at the oxygen sensor outputs, coolant temperature, airflow, calculated engine load, and inlet air temperature.

P2921 is a kind of Powertrain Trouble Code

Powertrain of a modern automobile, comprising engine (with exhaust system), transmission, drive shaft, suspension and the wheels. In a motor vehicle, the term powertrain or powerplant describes the main components that generate power and deliver it to the road surface, water, or air.

Common Causes of P2921

A common cause of code P2921 is the failure of Lamp Headlamp Low-Beam Circuit Open, but there are several other possible causes as well, such as ;

Damaged camshaft position (CMP) sensor
Faulty ignition coil (s)
Faulty Intake Valve Timing Control Solenoid Valve
Faulty oil control valve (OCV)

P2921 code for all cars

You can view according P2921 DTC for your car model. We selected several models to see obd2 solutions click and view it.

+P2921 Cadillac Osceola

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

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