Engine management system and exhaust purification system

Introduction

This chapter contains information on the following subjects:

Indicator lamps
Catalytic converter
Diesel particulate filter

Additional information and warnings

Indicator lamps

First read and observe the introductory information and safety warnings .

Lit up	Possible cause	Solution
	Engine management system fault (Electronic Power Control).	The engine should be checked by a qualified workshop as soon as possible.
	Diesel engine is preheating before starting.	⇒ Starting the engine.
	Fault in catalytic converter.	Decrease speed. Drive carefully to the next qualified workshop. The engine should be checked.
	Diesel particulate filter has become saturated with soot.	Drive for approximately 15 minutes in 4th gear (manual gearbox) or select D (automatic gearbox) at a speed of at least 70 km/h (45 mph). Please observe any applicable speed limits ⇒ . If the indicator lamp still does not go out, go to a qualified workshop.

Flashes	Possible cause	Solution
	Fault in engine management system (diesel engine).	The engine should be checked by a qualified workshop as soon as possible.
	Misfiring, which damages the catalytic converter.	Decrease speed. Drive carefully to the next qualified workshop. The engine should be checked.

Several warning and indicator lamps will light up briefly as a functional check when the ignition is switched on. They will switch off after a few seconds.

If the indicator lamps , or are lit up, fuel consumption may be higher and engine performance reduced.

Catalytic converter

First read and observe the introductory information and safety warnings .

The catalytic converter is used for exhaust gas post-treatment and helps to reduce exhaust emissions. To help ensure long-term functionality in the exhaust system and the catalytic converter:

Use unleaded petrol only.
Do not allow the fuel tank to run empty.
Do not overfill engine oil ⇒ Engine oil.
Do not tow-start the vehicle. Use jump leads ⇒ Jump-starting.

If you notice misfiring, uneven running or loss of power when the vehicle is moving, reduce speed immediately. The vehicle should be inspected at the nearest qualified workshop. If this happens, unburnt fuel can enter the exhaust system and escape into the atmosphere. The catalytic converter can also be damaged by overheating.

Even when the exhaust purification system is working perfectly, there may be a smell of sulphur from the exhaust in some conditions. This depends on the sulphur content of the fuel being used.

Diesel particulate filter

First read and observe the introductory information and safety warnings .

The diesel particulate filter filters out soot particles in the exhaust gas. The soot particles gather in the filter and are burnt under high temperatures periodically (regeneration). Heat produced can warm the engine.

Regeneration can cause noises, light smells and delay in radiator fan irrespective of the outside temperature, even after the engine is switched off.

To assist the regeneration of the diesel particulate filter, Volkswagen recommends that you avoid making only short journeys. In vehicles with automatic gearboxes the engine speed can increase while the vehicle is being driven. However, the indicator lamp will not light up.

Observe the following points to ensure that the exhaust system and the diesel particulate filter will work properly for a long time:

Only use diesel with low sulphur levels ⇒ Diesel.
Never use biodiesel, petrol or heating oil.
Do not allow the fuel tank to run empty.
Do not overfill engine oil ⇒ Engine oil.
Do not tow-start the vehicle. Use jump leads ⇒ Jump-starting.

Even when the exhaust purification system is working perfectly, there may be a smell of sulphur from the exhaust in some conditions. This depends on the sulphur content of the fuel being used.