P021E Diagnostic Trouble Code

P021E 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 P021E diagnostic trouble code may include:

Poor acceleration
Cherry red hot catalytic converter
Possible spark knock (detonation / pre-ignition)
If the DPF is not cleared the ECU will revert to the "Limp Home Mode" until the situation is corrected

Possible Causes :

A large air leak at or near the number one oxygen sensor would also cause a lean mixture.
Faulty IMRC actuator relay (if equipped)
A faulty oxygen sensor. This will set a code in itself, however, a faulty oxygen sensor does not automatically condemn the sensor. The code just means that the sensor signal was not within specifications. An air leak or any of the above will cause an erroneous signal. There is a multitude of O2 codes relating to O2 performance which gives a clue to the problematic area.

Repair Processes :

If all testing has passed so far yet you still have the same code, check your scan tool and see if it can open and close the IMRC valve. Look for missing ground strap or a rusty ground where the fuel tank is grounded to the frame. Check for damage to the wiring harness connector. 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.

Process Tips

Diagnostic trouble code P021E 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 P021E.

Fortunately, P021E is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

P021E Trouble Code For Specific Cars

P021E Rover 60 Ignition Coil C Primary Circuit Malfunction
P021E Honda N600 RCNT Solenoid Circuit Malfunction
P021E Bmw 2 Camshaft Position Sensor Circuit High Input
P021E Peugeot Bipper Electronic Throttle Monitor Malfunction
P021E Leblanc Mirabeau TCM Communication Circuit High
P021E Austin Princess Aux A/C Blower Speed 2 Circuit Failure
P021E Toyota Blade O2 Sensor Circuit Low Voltage (Bank 1 Sensor 1)