Volkswagen: heater blowing cold, coolant system, cold question

Question
QUESTION: iI HAVE A VW BORA 1999 THE FIRST TWO SETTINGS DONT COME ON BUT WHEN ITS ON 4 SETTING AT HAS STARTED TO BLOW JUST COLD AIR AND ONLY JUST GETS A BIT WARM CAN YOU PLEASE TELL ME WHAT IS WRONG  THANKYOU

ANSWER: There are three possibilities.  You may have air trapped in the cooling system or the level is low.  If air accumulates at the heater core, it will prevent coolant flow.  There are bleed points where air can be removed.  It could also be either a stuck thermostat or a bad impeller on the water pump.  However, if this were the case, you'd also see fluctuating temperature on the engine.  It could also be that the heater core is gunked up.  If you are not seeing engine temp problems, take it to a VW aware shop and have it flushed and filled with fresh G12 coolant.

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QUESTION: I HAVE JUST HAD THE  COOLANT SYSTEM FLUSH AND NEW ANTIFREEZE REPLACED ALSO THE THERMOSTAT IS FINE AND CHECKED FOR ANY AIR TRAPPED IN THE WATER PUMP AND THE HEATER STILL IS NOT GETTING HOT  HAVE YOU ANY MORE SUGGESTIONS TO HELP  THANKYOU   B SADLER

Answer
Did they bleed the air from the system where the heater hoses join up to the heater core?  When the engine is fully up to temperature, do both the hoses at the heater core feel hot?  The only other possibility is that the flapper control is broken.  I've never seen it happen, but it's possible.  Does the heater knob feel different when you turn it than it did before?