U2798 Diagnostic Trouble Code

U2798 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 U2798 diagnostic trouble code may include:

Carbon Buildup on O2 Sensor
Malfunction Indicator Lamp (MIL) illuminated
Hesitation upon acceleration
Engine surge

Possible Causes :

Rusty exhaust systems, cracked exhaust manifolds or damaged or missing gaskets or donuts will cause air leaks.
An air leak forward of the DPF will change the sensor readings resulting in the code
Some aftermarket accessories and performance modifications

Repair Processes :

Replace the oxygen sensor that is downstream from the catalytic converter on the side of the engine that does not contain cylinder #1. Also, if a oxygen sensor code stating "heater circuit malfunction" the sensor has most probably failed. Now, clear the codes and test-drive the vehicle to see if the code is reset. Look for damage to the tank indicating impact that may have damaged the fuel pump or sender.

Process Tips

Diagnostic trouble code U2798 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 U2798.

Fortunately, U2798 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

U2798 Trouble Code For Specific Cars

U2798 Willys-overland Whippet SCP (J1850) Invalid or Missing Data for Seat Motion / Control
U2798 Ford Thunderbird Mirror Passenger Vertical Switch Circuit Short To Ground
U2798 Mcc Forfour A/C Pressure Sensor Insufficient Pressure Change
U2798 Nissan Skyline Cruise Control On Signal Malfunction
U2798 Vauxhall Ventora Pressure Control Solenoid Failed Low
U2798 Peugeot 206
U2798 Ford Econovan MAP/MAF Throttle Position Correlation