U0801 Diagnostic Trouble Code

U0801 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 U0801 diagnostic trouble code may include:

Cherry red hot catalytic converter
Poor acceleration
The light may stay on or light intermittently as the DPF regenerates. The engine will be sluggish on acceleration.
Reduction in engine performance, especially at low RPM levels

Possible Causes :

An air leak forward of the DPF will change the sensor readings resulting in the code
Rusty exhaust systems, cracked exhaust manifolds or damaged or missing gaskets or donuts will cause air leaks.
Fuel with a large percentage of sulfur will clog the DPF quickly

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.

Process Tips

Diagnostic trouble code U0801 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 U0801.

Fortunately, U0801 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

U0801 Trouble Code For Specific Cars

U0801 Chery A5 Double Lock Timeout Failure
U0801 Renault Avantime Gear Shift Foward Actuator Circuit Low
U0801 Volvo 1500 SCP (J1850) Invalid or Missing Data for Climate Control (HVAC)
U0801 Shelby Super Cars Aero Intake Air Temperature Circuit Intermittent
U0801 Moretti 128 Battery Temp out of Range
U0801 Mahindra Xuv500 Traction Control Valve RF Circuit Short To Battery
U0801 Lancia Lambda Speed Wheel Sensor RR Input Circuit Failure