So.. I have problem with my car heating system. There are coming warm air from the driver's side but colder air from the passenger's side even when the heat is adjusted to blow hottest. When I took drive in cold winter air the passenger's side is like a refridgerator. I live in Finland.

 

Here are the things that has been done:

 

- Car have been at the repair shop for the coolant flushing so there are no dirt on the system.

- Thermostat was changed few months ago and the mechanic checked that the fluid is flowing through the system so waterpump should be ok. It has been changed about nine months ago.

- Heater core was changed in last year december.

- Passenger's side temperature flap motor is checked and it's fine.

- Obdeleven is not giving any fault codes from climatronic.

- All the climatronic sensors are ok.

- Mechanic also did the CO2 test for the coolant system and the test passed easily. So there are no gas leak on the system.

- Coolant fluid is not bubbling when the car is running.

 

I took off the temperature flap motor and i moved by hand the heating flap. It moves easily.

 

I also tested the passenger's side heating moving the temperature flap by hand when car was running. I put the flap in the hot blowing position. At the same time I was looking the climatronic sensor data from obdeleven. Passenger's side temperature is around 10 celsius degrees lower than the drivers side. When the coolant fluid starts to get warm and blowing also gets warmer the difference between driver's side and passenger's side gets even bigger.

 

One time at my tests I noticed that the coolant temperature suddenly dropped from 75 celsius degrees to aroun 50 celsius degrees. And simultaneously the temperature at the passenger's side dropped about 15-20 celsius degrees. Very strange...

 

When the car was at coolant flushing I asked the mechanic also to flush the heater core but I am not sure did they do it...

 

Is there some component on climatronic system that I can check or is the heater core flushing the only reasonable thing to do.. Also because of that I am not sure that did the mechanic flush the heater core. There can be some kind of clog inside of it.

 

It would be nice to figure out what causes the problem. I have been battling with this **it the whole winter and been driving with spare car. The winters in Finland can be tricky some times..

Not sure I can help with heating issues, but a fluctuating needle on a DSG is down to the DSG stat nearly all the time. Do a search on here. 

Maybe I have to be more accurate with the model. It is Skoda Suberb 2010 2.0 litre Tdi (170hp) and manual gearbox. 

 

Thanks for the reply.

I also noticed when I checked faults all over my car with obdeleven that the first cylinder glow plug gave error code... I guess this has nothing to do with the heating problem.. Or does it?

Has the car had the burst silikat bag issue?  Is the coolant header tank stamped with "mit silikat"? If the silikat bag fails the contents circulate turning the coolant a muddy colour and blocking fine tubes especially those contained within the heater matrix. Why was the heater core changed?

 

Also could be a good old fashioned air lock.

 

 

Edited 13 April, 20224 yr by bigjohn

Theres no silikat bag issue. The heater core was changed because it was full of dirt and wasn't cleanable. Is there some bleeding screws that I can bleed the system or is there another effective way to do it?

 

I asked the mechacnic who washed the coolant system that did he took off the heater core and washed it alone. He said that they did not took off heater core when they washed the system. They used some kind of washing liquid during the washing operation so I am pretty hopeful that the heater core is also clean... maybe...

 

One thing I noticed this day was when I checked the coolant level at expansion tank. Coolant fluid level was below the minimum level. I opened the tank cap and the fluid level rise between the max and min level. When the fluid reached the level above the fluid bubbled and there was pressure at the expansion tank. What conclusions I can make of that?

 

When the car is running i can hear light purl from the heater core. So there has to be air at the system.. Or do I have to fear that there are crack or some other problem at cylinder head..?