No heat

Elpres

Member
Hi guys, i have recently bought myself a a2, and there is not much heat in the cabin.. what to look for? Any pointers?
 
Hi,

Peraps you could provide a little more info.

Model year of TDi?
Ambient temperature?
How long has the engine been running for, and at what speed is it being driven at?
does the TDi have digital climate control or rotary heater controls?
If digital, what setting are being used?
If rotary, what setting are being used?
Is the temperature gauge inside the car showing 90°C?
Is there coolant in the header tank?
Have you access to a fault code reader or VCDS?

Cheers
Jeff
 
I'm guessing you've done the basic checks but for anyone that does not know, the heater and temp gauge can stop working due to a low (very) coolant level.
In cold ambients and short journeys the engine may not overheat so the lack of coolant may not be apparent

Cheers Spike
 
my money's on the flaps.

- Bret

Yes,

That is the most likely.

The only other thing I can think of is the thermostat stuck open?

I have experienced the blowing heater too hot occasionally (on previous A2s), but it is not that common to have it not blowing hot enough.

Steve B
 
So far i have found out that there is a ok amount of cooling fluid in the container and Its a digital clima control.
I will try to notice excatly how long it takes to get some warm air in the car.
 
Hi,

I specifically asked about the settings for the heater unit, ambient temps, engine temperature and the age of the vehicle in case your car has the Webasto additional diesel heater installed.

If your car has the Webasto it will be no older than a MY2002, because from MY2003 a ceramic electric additional heater was used instead.
If your car is old enough to have the Webasto you MUST ensure that the ECON button of the climate control unit is NOT illuminated. If this button is illuminated then the Webasto heater is disabled.

The Webasto addidtional heater is a diesel fired boiler that heats up the water in the cooling circuit of the engine.
The advantage of this system is that it gets the engine up to normal operating temperature quickly, therefore the ECU delivers an economic fuel mode quickly as well as allowing the cabin to get warm quickly too.
In its standard form in an A2, the Webasto only works when the engine is running and the ambient temperature is 5°C or lower and engine temperature is 70°C or lower.

Having access to VCDS (or a good OBDII diagnostic tool) will allow the user to view any faults that might be present for the Webasto as well as run tests on the various components of the system.
The Webasto unit does have a weak point, which is its glow-pin and burner. These items can be replaced, but are approx. £200 in parts alone, 1hr labout to strip and rebuild the Webasto and 4hrs labour to remove and refit in the vehicle.
The Webasto heater unit for the Audi A2 is specific for this car due to its electronics. The electronics (its ECU) cannot be purchased as a seperate part either from Audi or Webasto.

The cost of a new heater unit is in excess of £1000 + VAT
Model is a Webasto Thermo Top Z C/D
Part No. 8Z0 815 071

The Webasto has it's own exhaust system and fuel pump.
The exhaust pipe should fit onto the engine undertray near the front right wheel.
The Webasto fuel pump is not very well protected (it is located underneath the car just in front of right hand side rear wheel) and can rust away.
Fuel pump details:
Fuel Metering Pump
Part No. 4B0 963 303
£325 + VAT

As with any remote diagnostics, it is important to be provided with as much detailed and accurate information as possible so focused troubleshooting can begin quickly.

I hope this helps.

Cheers
Jeff
 
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Hi jeff, and thank you for taking the time writing all that.
It seems i have a non functional webasto heater. It minus 10* here at the moment and the Econ button is NOT illuminated, but nothing extra is started up under the bonnet, no sounds and no extra exhaust.
The car is from 2002, and today i let it idle for around 25min, with the clima on high and There was only a little warm air comming from the vents.

Could someone. Explain the expression :"flaps"?

With my expirience. (Mostly on older cars) the symptoms says its a stuck thermostat, and even though the webasto is not working the car should be providing warm air after 25min idling.
Am i right? And where would i find the thermostat?

Please forgive my english, im trying the best i can.
 
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i doubt youl get any heat with the tdi just idling, they run very cool i find , if i keep the revs below 2000rpm for my 15mile journey my temp gauge will not go above 60 degrees although ile have heat pouring from the cabin heater after a few miles , the engine will not get hot unless it is pushed above 2000rpm and then it will rise to the normal 90 degrees running temp and its the same with the webasto running too , they just dont make heat unless pushed a little ...

As you say its minus 10 id say it must take forever to get hot and certainly wont make the temp gauge move just on tickover

first thing i would check is all the fuses and earth points as can cause issues , then id be checking the dosing pump conections , underneath the car under the rear seat location , deisel cap side of the car , youl find a silver coloured alloy heat sheild underneath the A2, behind this youl see a small round pump with fuel hoses conected to it , remove and clean up the electrical plug, if you dont have access to vag com id even go as far as rigging up some wires with a 10amp inline fuse and test the pump works when connected directly to the battery, if the pump works ok id then go to the webasto unit under the bonnet, youl need to losen all the 10mm mounting bolts to be able to move the webasto out a little to gain access to the 2 wiring plugs , id sugest cleaning these aswell with electrical cleaner..

but without vagcom youl be hard pushed to find a fault without any fault codes stored in the webasto controller
 
i doubt youl get any heat with the tdi just idling, they run very cool i find , if i keep the revs below 2000rpm for my 15mile journey my temp gauge will not go above 60 degrees although ile have heat pouring from the cabin heater after a few miles , the engine will not get hot unless it is pushed above 2000rpm and then it will rise to the normal 90 degrees running temp and its the same with the webasto running too , they just dont make heat unless pushed a little ...

As you say its minus 10 id say it must take forever to get hot and certainly wont make the temp gauge move just on tickover

first thing i would check is all the fuses and earth points as can cause issues , then id be checking the dosing pump conections , underneath the car under the rear seat location , deisel cap side of the car , youl find a silver coloured alloy heat sheild underneath the A2, behind this youl see a small round pump with fuel hoses conected to it , remove and clean up the electrical plug, if you dont have access to vag com id even go as far as rigging up some wires with a 10amp inline fuse and test the pump works when connected directly to the battery, if the pump works ok id then go to the webasto unit under the bonnet, youl need to losen all the 10mm mounting bolts to be able to move the webasto out a little to gain access to the 2 wiring plugs , id sugest cleaning these aswell with electrical cleaner..

but without vagcom youl be hard pushed to find a fault without any fault codes stored in the webasto controller

Thanks, im trying to find some money for a vcds. But i will try your sugesstions in the meantime. Ill let you guys know how im doing.
 
Hi,

Your English is very good, so don't worry about that.

The diesel engines in our cars are very heat efficient, and therefore do not warm up quickly in colder temperatures.
This is why they have additional heaters fitted.
Also, if you are turning the heater on to full heat, any warmth that might be getting produced will just get pushed around the cabin water circuit and neither the engine or the interior will get any heat.

The best thing you can do (only because the Webasto is not working) is have the car idle with the Climate control turned off for about 5 mins and then sit in the car (still with the heater off) and hold the revs at 1500-2000 RMP for another 5 mins.
You should notice the temperature gauge rise a little by this time.
Turn on the climate to 20°C when the temperature gauge reaches 70°C and you should feel warm air.
The engine will need to be working at about 1800 RPM to keep warm in the temperatures you describe, so if you sit in traffic and the ambient temperature is -10°C the warm air will soon turn cool.
Once the engine is at normal operating temperature (90°C) and if you drive at about 1800 RPM, the engine alone (without the need for the Webasto) should hold temperature if the climate is set at 22°C.

The flaps:
The air conditioning unit in the A2 has flaps that control the direction of air and also the mix of cold and hot air.
If the temperature control flap is stuck you might only get hot air or cold air, depending where it is stuck.
If the temperature gauge is not getting to normal operating temp of 90°C, a flap issue is not the immediate concern.

If you can get the engine temperature gauge to reach 90°C with the heater turned off I'm sure you'll have heat in the cabin.
I would not look at the thermostat until it is certain that the car will not reach normal operating temperatures.

Cheers
Jeff
 
I did the test.
5 min idle then 5 min with 1800 rpm, still 60*, after another 3 min it Was 65*, and then there was warm air.

I did the same test with my wifes a2, and it was a bit quicker and the air a bit warmer.
 
Okay,

Once the engine gets up to temperature you'll have warm air.
You really need to have the car scanned so you know what is wrong with the Webasto heater.
If you get that fixed I'm sure you'll have a warm cabin and better MPG.
If the engine electronics (ECU) knows the engine is cold it will use a lot more fuel.

Good luck, and if you need help just ask

Cheers
Jeff
 
Note that displayed temperature is not the engine temperature. A few years ago, during a cold snap, I noticed that the displayed temperature on my 1.2Tdi would barely go beyond 60deg. However the heater was producing heat, so the thermostat must have been opening. A check with VCDS showed that the engine temperature was normal and somewhat above the temperature indicated by the gauge. At higher ambient temperatures the gauge normally shows a rock steady 90deg. The gauge temperature seems to be measured at the coolest (?) part of the system and with the heater acting as a second radiator, may be lower than that of the engine.

RAB
 
I finally Got myself a vcds, looking forward to investigate further regarding the pre heater.
 
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