U3850 Isotta-fraschini Tipo Diagnostic Trouble Code

U3850 Isotta-fraschini Tipo code definition:
U3850 is a kind of OBD-II Diagnostic U-Network Diagnostic Trouble Code for Isotta-fraschini Tipo.

U3850 Isotta-fraschini Tipo is described as Fuel System Too Rich, which basically means bank 1's oxygen sensor has detected a rich condition of fuel. This means there's not enough oxygen in the exhaust from too much fuel being delivered into the air and gas mixture for combusion. This is because the barometric pressure sensor is part of the MAF sensor. Sometimes, the MAF's sensing wire can accumulate and get covered with dirt, dust and/or oil residue, which can also lead to the error code.

Symptoms

Symptoms of a U3850 Isotta-fraschini Tipo diagnostic trouble code may include:

Malfunction Indicator Lamp (MIL) illuminated
Carbon Buildup on O2 Sensor
Poor fuel economy
Rich or lean exhaust

Possible Causes :

The Mass Airflow sensor will also cause this problem. Mass Airflow circuit malfunction.
Fuel with a large percentage of sulfur will clog the DPF quickly
Low fuel pressure caused by a clogged filter, failing fuel pump, failed fuel pressure regulator or clogged or leaking injectors.

Common Misdiagnoses

Vehicle Speed Output Circuit Problem
Cruise Control Servo Indicates Low Problem
A/C System High Pressure High Temperature Problem
PCM Stack Overrun Problem
Transmission Control Module Reprogrammable Memory Problem

Repair Processes :

Find out what kind of system you have and verify that voltage to the fuel level sensor is present at the fuel pump wiring harness. You might continue by connecting the scanner to the vehicle diagnostic connector and retrieving all stored codes and freeze frame data.

Process Tips

Diagnostic trouble code U3850 Isotta-fraschini Tipo 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 U3850 Isotta-fraschini Tipo.

Fortunately, U3850 Isotta-fraschini Tipo is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.