Greetings from Norway.

I have a 2016 skoda Fabia estate. 
When I turn on the heater, it is very weak in the left footwell.both airflow and temperature. It does not get as warm as the rest of the vents.
Does anyone else have this problem?

Regards!

10 days have passed and no help/ideas offered, oh well!

 

For airflow issues you would need to try to see if soundproofing carpet etc is partially blocking the LHS footwell outlet.

 

Temperature difference side to side, with this engine, can that not be connected with low coolant flow in general due to water pump issues?  Other TDI engines in the VW Group range, ie 2.0TDI seem to have this issue but it is caused sometimes by engine head/block casting sand not being completely removed after the casting process - and that ends up at the LHS of the heater matrix it seems, which sounds like a crazy situation that VW Group will attempt to correct for lots of money when just outside warranty, if flushing all the circuits does not give the required results, the heater matrix needs replacing to clear this blockage.

 

I would have thought that your car, supplied into Norway, also has an auxiliary heater I the heater box, but maybe that only gets used before the coolant has heated up fully, so is the LHS warmer when this auxiliary heater is running?

Just getting back to basics, if you have a cabin air filter when was it last changed? A clogged filter can give low air flow.