Driving and the environment
206change down into a lower gear or range (depending on the type of trans-
mission). This makes use of engine braking and relieves the brakes.•Never let the brakes “drag” by applying light pressure. Continuous 
braking will cause the brakes to overheat and the braking distance will 
increase. Apply and then release the brakes alternately.•Never let the vehicle run with the engine switched off. The braking 
distance is increased considerably when the brake servo is not active.•If the brake fluid loses its viscosity and is subjected to heavy use, 
vapour bubbles can form in the brake system. This reduces the efficiency of 
the brakes.•Non-standard or damaged front spoilers could restrict the airflow to the 
brakes and cause them to overheat. Before purchasing accessories please 
observe the relevant instructions  ⇒page 224, “Technical modifications”.•If a brake circuit fails, the braking distance will be increased consider-
ably. Contact a specialised workshop immediately and avoid unnecessary 
journeys.
Exhaust gas purification systemCatalytic converter*To maintain the useful life of the catalytic converter
– Use only unleaded petrol with petrol engines, as lead damages  the catalytic converter.
– Do not let the fuel get too low in the tank. – For engine oil changes, do not replenish with too much engine oil 
⇒page 237, “Topping up engine oil   E”.
– Never tow the vehicle to start it, use jump leads if necessary  ⇒page 281.
If you notice misfiring, uneven running or loss of power when the vehicle is 
moving, reduce speed immediately and have the vehicle inspected at the 
nearest specialised workshop. In general, the exhaust gas warning lamp will 
light up when any of the described symptoms occur  ⇒page 77. If this 
happens, unburnt fuel can enter the exhaust system and escape into the envi-
ronment. The catalytic converter can also be damaged by overheating.
WARNING
The catalytic converter reaches very high temperatures! There is a risk of 
fire.•Never park where the catalytic converter could come into contact with 
dry grass or flammable materials under the vehicle.•Do not apply additional underseal or anti-corrosion coatings to the 
exhaust pipes, catalytic converter or the heat shields on the exhaust 
system. These materials could catch fire when the vehicle is being driven.Caution
Never run the fuel tank completely dry because the irregularity of the fuel 
supply may cause ignition problems. This allows unburnt fuel to enter the 
exhaust system, which could cause overheating and damage the catalytic 
converter.
For the sake of the environment
Even when the emission control system is working perfectly, there may be a 
smell of sulphur from the exhaust gas under some conditions. This depends 
WARNING (continued)
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