Heaters blowing cold air even when cars warm

**JordanAudiA3** · 15-01-2014,08:38 AM

Please read carefully people, i have a 2004 Audi A3 2.0 TDi BKD, my heaters are blowing out cold air evan though my engine is at 90, sometimes if im on the motorway the heaters will be slightly warmer (no where near as warm as they should be). Also since i got the car 8 months back its been a real thirsty car with water, started off where i would have to top it up monthly then forghtnighlty then weekly now its every few days.

Occasionally the car will overheat on the motorway im not sure if this is due to a low water level or not just hoping for some advice from people get this problem sorted, its winter and im freezing and cant go on long drives because of this!! Cheers guys looking forward to hearing a response

Sent from my iPhone using Tapatalk MERRY CHRISTMAS!!!

**DarkBunny** · 15-01-2014,08:56 AM

From previous experience on other cars, it's showing all the signs of a blown head gasket.

You need get a compression test done on all cylinders as it may well be water going out via the piston, rather than into your oil.

You need to sort sooner rather than later, as I've damaged heads by leaving one in the past...

**Kar Krazy** · 15-01-2014,08:58 AM

Hi J,

It sounds like you have a water leak somewhere, and it's getting worse. The car uses the water in the cooling system to bring heat from the engine to your heater, so maybe the heater hoses are blocked by an "air lock", meaning a bubble of air that refuses to move despite water pressure trying to shift it. Loss of coolant may have caused the air lock. The antifreeze in the coolant not only prevents freezing, it also inhibits corrosion in the cooling system. If you have been topping it up with plain water, then you may get corrosion blocking part of the system. This is another thing that could cause your heater to stop giving heat, if the heater matrix (the little radiator that warms the air inside the car) is blocked on the inside by this corrosion.

**JordanAudiA3** · 15-01-2014,10:41 AM

Originally Posted by DarkBunny

From previous experience on other cars, it's showing all the signs of a blown head gasket.

You need get a compression test done on all cylinders as it may well be water going out via the piston, rather than into your oil.

You need to sort sooner rather than later, as I've damaged heads by leaving one in the past...

Like i said pal its been happening for the past 8 months just been getting worse surely this isnt the head and its something else? How often do they go?

Thanks for your help people!!

**DarkBunny** · 15-01-2014,10:44 AM

Originally Posted by JordanAudiA3

Like i said pal its been happening for the past 8 months just been getting worse surely this isnt the head and its something else? How often do they go?

Thanks for your help people!!

Still worth checking compressions to rule it out. The one on my Rover had gone for well over 6 months before final diagnosis, and my Evo had gone for 4 months before finding out the water was going into the piston (that wasn't losing water incredibly!). The Evo only had a poor start but no other symptoms at all.

**JordanAudiA3** · 15-01-2014,11:06 AM

Originally Posted by DarkBunny

Still worth checking compressions to rule it out. The one on my Rover had gone for well over 6 months before final diagnosis, and my Evo had gone for 4 months before finding out the water was going into the piston (that wasn't losing water incredibly!). The Evo only had a poor start but no other symptoms at all.

Mine some times struggles to start aswell could this be something to do with water.

Thanks for your help people!!

**DarkBunny** · 15-01-2014,11:11 AM

Originally Posted by JordanAudiA3

Mine some times struggles to start aswell could this be something to do with water.

Thanks for your help people!!

Potentially, yes. The Evo would start after a few turns, then rough idle for about 20 seconds. This was due to water going into the piston whilst the engine wasn't running.

Funnily enough, then compression was out in that piston and when we looked into the block (using a camera), there was a clean patch on the piston top (hence the water ingress).

**b206** · 15-01-2014,12:37 PM

1. Any gunk under the oil cap or on the dipstick ?
2. What colour is the coolant ?
3. Excessive condensation from exhaust ?
4. When you leave the car, does the water level change ?

If you are filling her up with water on a daily basis its a fairly big leak and you should be able to see where the water is coming from - if not it sounds like a head gasket issue.
Get it sniff tested, quickest and cheapest way.

**JordanAudiA3** · 15-01-2014,07:06 PM

Originally Posted by b206

1. Any gunk under the oil cap or on the dipstick ?
2. What colour is the coolant ?
3. Excessive condensation from exhaust ?
4. When you leave the car, does the water level change ?

If you are filling her up with water on a daily basis its a fairly big leak and you should be able to see where the water is coming from - if not it sounds like a head gasket issue.
Get it sniff tested, quickest and cheapest way.

No gunk whatsoever under the oil cap matey or on the end of the dipstick, the coopant is an orangey colour, and whats a sniff test?

Took it to garage earlier and they told me its more than likely a water pump failure, the car wont over hear if the blowers are on hot unless ive been on the motorway for a while

Thamks

Thanks for your help people!!

**b206** · 15-01-2014,07:25 PM

Sniff test is where the garage tests the coolant for exhaust gasses.
Sounds like you have corrosion somewhere if the coolant is orange (should be pink). If it turns out to be the pump, make sure they use genuine parts as the non-genuine pumps are crap! - you may as well have the cam belt changed at the same time.