U140A Diagnostic Trouble Code

U140A 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 U140A diagnostic trouble code may include:

Diminished fuel efficiency
Fuel pressure too high
Malfunction Indicator Lamp (MIL) illuminated
Hesitation upon acceleration

Possible Causes :

A plugged converter will cause of host of driveability problems as well as set this code. A severely plugged converter will result in the inability to increase rpm when under load. Look for a code such as P0421 -- catalytic converter efficiency below threshold if the converter indicating a faulty converter.
Dirty air cleaner element Damaged DPF
Faulty IMRC actuator/sensor

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. 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. Look for damage to the tank indicating impact that may have damaged the fuel pump or sender.

Process Tips

Diagnostic trouble code U140A 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 U140A.

Fortunately, U140A is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

U140A Trouble Code For Specific Cars

U140A Bmw Mini Clutch Pedal Switch B Circuit High
U140A Alfa Romeo Arna Accessory Delay Relay Coil Circuit Failure
U140A Nissan Kubistar Code Word Unregestered
U140A Lada 117 Servo Motor Potentiometer Vent Circuit Short To Ground
U140A Toyota Aygo O2 Sensor Circuit High Voltage (Bank 2 Sensor 1)
U140A Oldsmobile Trofeo Damper LR Circuit Failure
U140A Reliant Sst Gate Select Position Circuit Low