U228U Diagnostic Trouble Code

U228U 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 U228U diagnostic trouble code may include:

Faulty or damaged wiring
The engine oil will exhibit dilution from the ECUs attempts to increase engine temperature. Some vehicles advance the fuel injection timing slightly after top center to afterburn a small amount of fuel to increase exhaust temperatures. Some of this fuel enters the crankcase. When the ECU determines the necessity to regenerate the DPF, the service life of the oil be shortened significantly
Poor fuel economy
Diminished fuel efficiency

Possible Causes :

The Mass Airflow sensor is a hot wire that senses the volume of air entering the intake manifold. The computer uses this information to control fuel mixture.
Defective ECU strategies or components will prevent proper regeneration
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 :

Look at the plug wires to make sure they are not burnt or laying on the exhaust. 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. Look for rubbing, scraping, bare wires, worn spots or melted plastic connectors. Pull the connectors apart and carefully look at the terminals (the metal parts) inside the connectors.

Process Tips

Diagnostic trouble code U228U 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 U228U.

Fortunately, U228U is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

U228U Trouble Code For Specific Cars

U228U Italdesign Tapiro SCP (J1850) Single Ended (+) Circuit Failure
U228U Bmw Six Clutch Switch Input Circuit Malfunction
U228U Spectre R45 Lamp Brake Warning Output Circuit Short To Battery
U228U Chrysler Thunderbolt Exhaust Pressure Control Valve High
U228U Mercury Sable Air Suspension Reservoir Pneumatic Failure
U228U Bmw Serie 2 Clutch Position Sensor Circuit High Malfunction
U228U Warwick Buick SCP (J1850) Invalid or Missing Data for Memory Storage