U3722 Diagnostic Trouble Code

U3722 is a kind of OBD-II Diagnostic U-Network 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 U3722 diagnostic trouble code may include:

Fuel pressure too low
Rich or lean exhaust
Diminished fuel efficiency
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)
Faulty IMRC actuator/sensor

Repair Processes :

Check to make sure they are not burnt or corroded. If in doubt, get some Electrical Contact cleaner at any parts store if cleaning of the terminals is needed. With the valve disconnected, the red voltmeter lead should be attached to the IMRC valve power wire and the black voltmeter lead connected to ground. 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 U3722 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 U3722.

Fortunately, U3722 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

U3722 Trouble Code For Specific Cars

U3722 Opel Corsa B Decklid Release Circuit Short To Battery
U3722 Hillman Hunter Passenger's Seatbelt Tension Reducer Circuit Short to Ground
U3722 Westfield Zei
U3722 Geely Bo O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 3)
U3722 Lanchester Sprite Speed Wheel LR Comparison Failure
U3722 Marmon 34 Transmission 4-Wheel Drive Low Indicator Open Circuit
U3722 Tvr 390 Power Door Lock Circuit Failure