C0340 Lancia Thema Diagnostic Trouble Code

C0340 Lancia Thema code definition:
C0340 is a kind of OBD-II Diagnostic C-Chassis Diagnostic Trouble Code for Lancia Thema.

C0340 Lancia Thema is a DTC or a diagnostic trouble code. It is a check engine light code which indicates that the catalyst's system efficiency is less than the required threshold. In simple terms, it means that more pollution is added into the air than what was supposed to be because of your car. Other serious codes may cause this code to pop up, and they may come with dangerous drivability issues that may expose you to safety risks and cause damage to the engine in the long run.

Symptoms

Symptoms of a C0340 Lancia Thema diagnostic trouble code may include:

Misfire
Misfire
The light may stay on or light intermittently as the DPF regenerates. The engine will be sluggish on acceleration.
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
An air leak forward of the DPF will change the sensor readings resulting in the code

Common Misdiagnoses

IC Circuit High Voltage Problem
Control Module Throttle Actuator Position Performance Problem
Air Conditioning (A/C) Clutch Feedback Circuit High Voltage Problem
Cruise Vehicle Speed/Set Speed Difference Too High Problem
PCM Stack Overrun 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. Look at the plug wires to make sure they are not burnt or laying on the exhaust. Pack the connector cavity with dielectric silicone compound (same stuff they use for light bulb sockets and spark plug wires) and reassemble.

Process Tips

Diagnostic trouble code C0340 Lancia Thema 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 C0340 Lancia Thema.

Fortunately, C0340 Lancia Thema is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.