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Driving and operating
As soon as the natural gas tank is
empty, petrol operation is
automatically engaged until the
ignition is switched off.
If the natural gas tank is not refuelled,
the system must be manually
switched to petrol operation before
the engine is started-up again. This
will prevent damage to the catalytic
converter (overheating caused by
irregular fuel supply).
If the selector switch is operated
several times within a short time, a
switchover block is activated. The
engine remains in the current
operating mode. The block remains
active until the ignition is switched off.
A slight loss of power and torque can
be expected during petrol operation.
You must therefore adapt your driving
style (e.g. during overtaking
manoeuvres) and vehicle loads (e.g.
towing loads) accordingly.
Every six months run the petrol tank
down until control indicator
Y
illuminates, then refuel. This is
necessary to maintain fuel quality as
well as system function necessary for
petrol operation.
Fill the tank completely at regular
intervals to prevent corrosion in the
tank.
Fuel for liquid gas
operation
Liquid gas is known as LPG
(Liquefied Petroleum Gas) or under
its French name GPL (Gaz de Pétrole
Liquéfié). LPG is also known as
Autogas.
LPG consists mainly of propane and
butane. The octane rating is between
105 and 115, depending on the
butane proportion. LPG is stored
liquid at around 5 - 10 bar pressure.
The boiling point depends on the
pressure and mixing ratio. At ambient
pressure, it is between -42 °C (pure
propane) and -0.5 °C (pure butane).
Caution
The system works at an ambient
temperature of approx. -8 °C to
100 °C.
Full function of the LPG system can
only be guaranteed with liquid gas
which complies with the minimum
requirements of DIN EN 589.
Fuel selector
Pressing the LPG button switches
between petrol and liquid gas
operation as soon as the required
parameters (coolant temperature,
