U3956 Audi 80 Diagnostic Trouble Code

U3956 Audi 80 code definition:
U3956 is a kind of OBD-II Diagnostic U-Network Diagnostic Trouble Code for Audi 80.

U3956 Audi 80 is triggered when the bank 1 camshaft position sensor doesn't match the signal from the crankshaft position sensor. Any code that causes the vehicle's engine to die while running should be fixed as soon as possible, as it can be dangerous for both the vehicle and the passengers of the vehicle.

Symptoms

Symptoms of a U3956 Audi 80 diagnostic trouble code may include:

Hesitation upon acceleration
Excessive exhaust leak
Rich or lean exhaust
The light may stay on or light intermittently as the DPF regenerates. The engine will be sluggish on acceleration.

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.
Some aftermarket accessories and performance modifications

Common Misdiagnoses

Exhaust Gas Recirculation System Valve 1 Problem
BBV Sensor Circuit Low Voltage Problem
Transmission Engaged At High Throttle Angle Problem
Cruise Inhibit Control Circuit Problem
TFP Valve Position Switch-Drive Without Drive Ratio Problem

Repair Processes :

You might continue by connecting the scanner to the vehicle diagnostic connector and retrieving all stored codes and freeze frame data. 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 U3956 Audi 80 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 U3956 Audi 80.

Fortunately, U3956 Audi 80 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.