Illustration: Malfunction or Smoking In the Independent/Auxiliary Heating

Illustration: Malfunction or Smoking In the Independent/Auxiliary Heating

Cause 1
The problem can be caused by incorrectly installed underbody panelling. Illustration 1 shows incorrectly installed underbody panelling without an opening for the exhaust system end pipe. Illustration 2 shows the correct underbody panelling with an opening for the exhaust system end pipe.












Cause 2
If the air inlet hose is twisted, as shown in illustration 3, the independent heating is not receiving sufficient air. This leads to unclean and incomplete fuel combustion. Due to the incomplete combustion, surplus fuel enters the heater and the exhaust system. This means that the heater starts to produce soot, which in turn leads to smoking and failure of the independent heating.
Causes 1 and 2 mean that the insulating material in the muffler of the exhaust system can be soaked with fuel. This means that smoking can still occur after replacement of the heater or underbody panelling. In this case, it is recommended to replace the muffler