Cooling issue/oddity

[cmal1001]

So a few days ago i realised my hot air wasn't blowing hot. Coolant level seemed good (it was between the min and max line as far as i could tell) but today i just got back from a reasonably short drive and the radiator/coolin fan kicked in after i shut the engine off. Thought nothing more of it so i drove the car another 7 miles or so, but i noticed this time when i was just starting to pull away i could hear a slight/faint rubbing sound, once the car got moving obvious road sounds masked it (ive noticed it only makes that noise when you actually drive, not when you rev stationary) and again the fan stayed on for about 1 minute after parking. Dash temp shows bang on 90

Also its an 07 2.0 TDI plate so im fairly certain that model doesnt have DPF so i am assuming its not a DPF regen thats been interrupted
So what sort of demons are we dealing with here?

TIA

 

[B7Tourer]

I've just sorted a similar problem, after having no heat for a while (only noticed this winter) - a new heater matrix fitted. I don't know why your radiator fans are kicking in or rubbing noise though, since my car had no other problems, except no cabin heat. I swear though that the car reaches 90 degrees much quicker now after starting up though. I did replace the air con compressor at the same too, since I had recently lost that too and after listening to that clatter in 'Econ' (perished rubber in the pulley) ever since I got the car, it is bliss to have a smooth sound all the time now.

 

[cmal1001]

I've just sorted a similar problem, after having no heat for a while (only noticed this winter) - a new heater matrix fitted. I don't know why your radiator fans are kicking in or rubbing noise though, since my car had no other problems, except no cabin heat. I swear though that the car reaches 90 degrees much quicker now after starting up though. I did replace the air con compressor at the same too, since I had recently lost that too and after listening to that clatter in 'Econ' (perished rubber in the pulley) ever since I got the car, it is bliss to have a smooth sound all the time now.

Hey mate. Yeah i thought maybe the heater matrix, but upon further inspection inside the coolant tank there are like these mineral looking blocks exposed, the coolant sits around 1-2cm below them. And ofcourse the tank is opaque so you cant really see if the liquid is between the max and min. Not to mention the coolants colour is a bit ..anaemic looking. does it need topped up do you think? Is there any possible way that the dash temp could be showing a faulty reading and my piston rings are eating away the engine haha thats what concerns me

 

[B7Tourer]

I'm not really an expert but you should easily be able to see the level in your header tank and the coolant should be a healthy pink - it sounds like you need a coolant flush and change soon. The temp gauges are not very accurate, as far as I know and it sounds like your engine is definitely slightly overheating - hence the fans kicking in. When and if you do change the coolant you could try reverse flushing the heater matrix too and if it was my car get to the bottom of that rubbing too. I didn't bother with this, electing to replace it with new oem, same as not bothering to muck about with a new pulley on the compressor, since in the end the clutch or unit went anyway. Good luck mate.

 

[cmal1001]

I'm not really an expert but you should easily be able to see the level in your header tank and the coolant should be a healthy pink - it sounds like you need a coolant flush and change soon. The temp gauges are not very accurate, as far as I know and it sounds like your engine is definitely slightly overheating - hence the fans kicking in. When and if you do change the coolant you could try reverse flushing the heater matix too. I didn't bother with this, electing to replace it with new oem, same as not bothering to muck about with a new pulley on the compressor, since in the end the clutch or unit went anyway. Good luck mate.

I think ill do that first. I'll probably change the temp sensors too and the thermostat. Do you know of any guides how to do the coolant change?

 

[redVENGEANCE]

Hey mate. Yeah i thought maybe the heater matrix, but upon further inspection inside the coolant tank there are like these mineral looking blocks exposed, the coolant sits around 1-2cm below them. And ofcourse the tank is opaque so you cant really see if the liquid is between the max and min. Not to mention the coolants colour is a bit ..anaemic looking. does it need topped up do you think? Is there any possible way that the dash temp could be showing a faulty reading and my piston rings are eating away the engine haha thats what concerns me

I think you are low on coolant. I use those 3 blocks as a guide and make sure they are just covered with coolant.

Sent from my SM-G950F using Tapatalk

 

[B7Tourer]

I don't really buddy, since I'm my days to muck about in drives, are over now. I use a good trusted independent down the road - I wish I still did stuff myself it would have saved me a fortune on an old car that's now a labour of love not value, ha ha. I do all the detailing like fitting gadgets, switches lights etc. myself but that's about it. I do have a Haynes manual that I think details it pretty good though - it's much like any other car, I suppose. You might get hold of one of them? Or I am certain one of the other far more knowledgeable fellas here will chip in. The coolant should be flushed and changed at least every 5 years.

 

[cmal1001]

I think you are low on coolant. I use those 3 blocks as a guide and make sure they are just covered with coolant.

Sent from my SM-G950F using Tapatalk

Yeah i thought that too. Ill get the coolant changed. Not sure why im hearing this noise though.

 

[B7Tourer]

Yeah i thought that too. Ill get the coolant changed. Not sure why im hearing this noise though.

What kind of noise is it exactly - have you observed the accessory belt in motion? Water pump? Or something else? I've had no major problems with my 2.0 TDI BRE, now at 230K but I have had to change ALL the front pulleys in my ownership. And a very worthwhile investment that was too.

 

[Charlie Farley]

When your engine is running and upto normal operating temp , hold the inlet then outlet hoses that feed the heater matrix, with your heater set to hot and on full you should have both hot .

 

[Charlie Farley]

The B7 heater matrix's are notorious for airlocks, I'm not saying it that as you don't mention anything prior repair wise that would cause an airlock to develop but it's an Audi so anything and everything is possible.

 

[Charlie Farley]

Could be a blockage aswell.
Depending on the mileage don't write off the matrix just like that, you just need to eliminate the obvious first, so if you have hot water flowing in and out of the matrix, it won't be the matrix, and you need to look outside the box as they say.

 

[cmal1001]

What kind of noise is it exactly - have you observed the accessory belt in motion? Water pump? Or something else? I've had no major problems with my 2.0 TDI BRE, now at 230K but I have had to change ALL the front pulleys in my ownership. And a very worthwhile investment

Hard to say, it might very well have been there before but its like just as you pull away its a very very quiet faint rubbing/grinding noise. I've pulled the cover off the belts and they all seem okay, acc belt is fine. Mines is at 102k miles, bought it on a whim for 1500 quid (with no service history) its an S line in red and its in amazing condition outside and in, have put 2000k miles on it with no problems

 

[cmal1001]

When your engine is running and upto normal operating temp , hold the inlet then outlet hoses that feed the heater matrix, with your heater set to hot and on full you should have both hot .

I guess ill need a hand from someone to check the hot air? ill try that. im not too fussed about trivial things i am just concerned that my engine is over heating :/

 

[cmal1001]

Should probably mention aswell i went to check under the bonnet and it was roasting in there... the engine cover was almost too hot to the touch

 

[Charlie Farley]

To be honest chap, I think you would be wise to get the car scanned properly with vcds and see what is happening, current real-time engine temp etc , don't rely on the gauge.
It will also report fan issues and the such like.
You don't need to check the heater fan air temp, just hold the inlet and outlet hoses that pass through the bulkhead just next to the battery.
If they are both hot then that eliminates the matrix as the lack of heat inside the car, the engine bay overall temp may be more of a concern so get it scanned.

 

[Charlie Farley]

If you only get the odd noise when driving and nothing when stationary then that kinda eliminates the engine itself, so look for other visible signs of wear/contact etc in the engine bay and beyond.

 

[B7Tourer]

Hard to say, it might very well have been there before but its like just as you pull away its a very very quiet faint rubbing/grinding noise. I've pulled the cover off the belts and they all seem okay, acc belt is fine. Mines is at 102k miles, bought it on a whim for 1500 quid (with no service history) its an S line in red and its in amazing condition outside and in, have put 2000k miles on it with no problems

Sounds a good find and buy but it does mean it has done less than 7K a year and probably sat around for some of that. Do you know, have a record, if the timing belt/water pump were changed at 75K.

 

[cmal1001]

Sounds a good find and buy but it does mean it has done less than 7K a year and probably sat around for some of that. Do you know, have a record, if the timing belt/water pump were changed at 75K.

Thats a question the seller couldnt answer, im assuming the timing belt is under the plastic cover at the front of the engine? it looks in okay condition its not shiny or fraying

 

[B7Tourer]

Thats a question the seller couldnt answer, im assuming the timing belt is under the plastic cover at the front of the engine? it looks in okay condition its not shiny or fraying

I'm not sure (do you mean the plastic cover at the bottom?) In any case it's not really a reliable indicator, since you can't tell the condition of the water pump, tensioner etc. When I bought my B7, I knew absolutely nothing about them and it's documentation was patchy - but everyone said the very 1st thing you must do, without fail, is cambelt/water pump, unless there has been proof it has been done recently.