'89 80 B3 no heat

00mike00 · 23-02-18, 11:35 AM

The Audi 80 has been running rather well but sadly there appears to be something wrong with the heater.
I’ve got decent coolant levels and mix, when I bought the car the heater wasn’t great. Slowly but surely the heater has nearly all but failed.
I’ve had a matrix die on me before on an Opel Monza, it took me almost 12 hours over two weekends to do the job, so I’m obviously not keen on doing such a job again.

There doesn’t appear to be any water inside the car, so I’m looking for advice on diagnosing what’s wrong. The dial actually only works on number 3 and 4, so I was wondering if something as simple as the dial assembly could cause an issue.

Duffy3074 · 23-02-18, 06:08 PM

Could be 2 different problems.

You've checked for hot water going into the matrix by feeling the pipes going through the bulkhead?
The controls are cable operated and if you are getting cold air blowing through but can't get hot air then you've either got a completely blocked matrix or the flap that pushes the air through the matrix on the hot setting isn't working.
When you put the control from cold to hot you should be able to hear the flap moving over and feel the resistance through the control as you put it over

Mellis46 · 23-02-18, 06:31 PM

As Duffy mentions, The matrix doesn't have to be leaking to be knackered, could be blocked? The previous owner of my 90 2.2E had tried Radweld to cure its leaky radiator. The radiator still leaked but the matrix was sealed up pretty well.. There must have been a route through as the pipes still got warm.

You could try flushing / back flushing, see if any gunk comes out?

00mike00 · 23-02-18, 10:58 PM

Quote:

Originally Posted by Duffy3074

Could be 2 different problems.

You've checked for hot water going into the matrix by feeling the pipes going through the bulkhead?
The controls are cable operated and if you are getting cold air blowing through but can't get hot air then you've either got a completely blocked matrix or the flap that pushes the air through the matrix on the hot setting isn't working.
When you put the control from cold to hot you should be able to hear the flap moving over and feel the resistance through the control as you put it over

Thanks for the input chaps, I'll try some if not all of this tomorrow.
I'll report back!

00mike00 · 25-02-18, 07:18 PM

Yesterday I changed the coolant in the 80. I tried flushing the matrix but I don't have the adequate kit since moving into my new place.
With the level back to normal and good run, I have it running back at a decent, stable temperature. The two pipes going into the matrix get hot but I'm still only getting lukewarm air coming through into the car.
I'm dreading a matrix swap, so any advice welcome.

Davids · 25-02-18, 07:33 PM

I had much the same issue in my Coupe ( 91 )
In the end bit the bullet and took the dash and everything out to get to the heater.
Actually it wasn't that bad, took about 4 hours.
It was the foam has disintegrated on the flaps in the heater, took longer to clean the poxy glue and backing off the flaps than take the dash out. I think this fault is well documented on here.
Once done the heater is toastie now.
One tip though, where the plastic heater air casing mates up to the dash air ducts, sort of a square shape, over the years this must have got warped as I had at least a 5mm gap at the bottom and one side and no amount of tweaking could get them to seal, this would have meant all the air would have blown out behind the dash.
I sealed it with some air con duct tap we use at work.

Hope you can get yours sorted with out resorting to this.
Cheers
David

msh · 25-02-18, 07:36 PM

The cause could be just as well coming from foam in which heater flaps are covered, being totally disintegrated due to age, leaving bare metal with big holes and allowing at least half of air bypass matrix even when set to full hot. It could be caused by age alone, and if there was heater matrix failure in past, without flaps being recovered at the same time as heater matrix change, there would be failed flaps as well, accelerated by hot steam. So, if you remove heater from the car and see that central flap [the one which do or doesn't block panel front outlets] is bare, prepare to split the heater and re-cover the flaps. Some use duct tape, but more proper material is drywall amortisation tape, widest one, comes in big roll, can be bought in construction stores, and that roll is enough for at least 20 heaters...

As for aftermarket heater matrixes - care must be taken, as there are some "souther" variety matrixes, with low count of ribs, resulting in low heat output. I for this reason have two heater matrixes to compare - crappy audi B series one and OEM mk2 golf one [identical, apart from outlet angle] - the difference between the two is quite noticeable.

00mike00 · 25-02-18, 07:45 PM

Quote:

Originally Posted by Davids

I had much the same issue in my Coupe ( 91 )
In the end bit the bullet and took the dash and everything out to get to the heater.
Actually it wasn't that bad, took about 4 hours.
It was the foam has disintegrated on the flaps in the heater, took longer to clean the poxy glue and backing off the flaps than take the dash out. I think this fault is well documented on here.
Once done the heater is toastie now.
One tip though, where the plastic heater air casing mates up to the dash air ducts, sort of a square shape, over the years this must have got warped as I had at least a 5mm gap at the bottom and one side and no amount of tweaking could get them to seal, this would have meant all the air would have blown out behind the dash.
I sealed it with some air con duct tap we use at work.

Hope you can get yours sorted with out resorting to this.
Cheers
David

Thanks for both replies guys...I have changed a matrix on an '83 Opel Monza and it took me around 10 hours because the thing comes off in one and was very complicated.
I pretty much understand what has been said here but are there any threads i can look at to give me photos, or more detail?

Where should I get my replacement matrix from?

Mellis46 · 25-02-18, 07:48 PM

once everything is stripped down enough to be looking at iffy heater flaps, its not that much more work to change the matrix, cleaning out all the bits of shredded leaves etc that will also be in there. If the matrix hasnt already been done it will be well on its way based purely on age, you might want to consider doing it anyway...

Think Duffy managed to source a matrix for literally a couple of pounds! Amazon IIRC?

00mike00 · 25-02-18, 08:10 PM

Quote:

Originally Posted by Mellis46

once everything is stripped down enough to be looking at iffy heater flaps, its not that much more work to change the matrix, cleaning out all the bits of shredded leaves etc that will also be in there. If the matrix hasnt already been done it will be well on its way based purely on age, you might want to consider doing it anyway...

Think Duffy managed to source a matrix for literally a couple of pounds! Amazon IIRC?

Ok thanks, I guess i just start attacking it where i can see fixings then. I was hoping someone had made some kind of album or something.
How do i ensure i'm getting the correct matrix? I did a quick search and found one for a B4...mines an '89 B3.

Cheers

23-02-18, 06:31 PM	#3
Mellis46 Aero Advocate Classic Audi Club Member Join Date: Aug 2014 Location: Lancashire Posts: 1,448	As Duffy mentions, The matrix doesn't have to be leaking to be knackered, could be blocked? The previous owner of my 90 2.2E had tried Radweld to cure its leaky radiator. The radiator still leaked but the matrix was sealed up pretty well.. There must have been a route through as the pipes still got warm. You could try flushing / back flushing, see if any gunk comes out? __________________ -1987 90 2.2E / Sapphire Blue (Rest in Pieces) -1989 90 quattro with Sport Equipment / Satin Black -1997 A4 Avant quattro TDI 110 / Tropical Green (Sold)

25-02-18, 07:48 PM	#9
Mellis46 Aero Advocate Classic Audi Club Member Join Date: Aug 2014 Location: Lancashire Posts: 1,448	once everything is stripped down enough to be looking at iffy heater flaps, its not that much more work to change the matrix, cleaning out all the bits of shredded leaves etc that will also be in there. If the matrix hasnt already been done it will be well on its way based purely on age, you might want to consider doing it anyway... Think Duffy managed to source a matrix for literally a couple of pounds! Amazon IIRC? __________________ -1987 90 2.2E / Sapphire Blue (Rest in Pieces) -1989 90 quattro with Sport Equipment / Satin Black -1997 A4 Avant quattro TDI 110 / Tropical Green (Sold)

23-02-18, 06:08 PM	#2
Duffy3074 4 ring whore! Classic Audi Club Member Join Date: Aug 2015 Location: Dalgety Bay, Fife Posts: 2,078	Could be 2 different problems. You've checked for hot water going into the matrix by feeling the pipes going through the bulkhead? The controls are cable operated and if you are getting cold air blowing through but can't get hot air then you've either got a completely blocked matrix or the flap that pushes the air through the matrix on the hot setting isn't working. When you put the control from cold to hot you should be able to hear the flap moving over and feel the resistance through the control as you put it over

25-02-18, 07:18 PM	#5
00mike00 Grown up member Classic Audi Club Member Join Date: Jan 2018 Posts: 33	Yesterday I changed the coolant in the 80. I tried flushing the matrix but I don't have the adequate kit since moving into my new place. With the level back to normal and good run, I have it running back at a decent, stable temperature. The two pipes going into the matrix get hot but I'm still only getting lukewarm air coming through into the car. I'm dreading a matrix swap, so any advice welcome.

25-02-18, 07:33 PM	#6
Davids 4 ring whore! Join Date: Jan 2017 Posts: 3,124	I had much the same issue in my Coupe ( 91 ) In the end bit the bullet and took the dash and everything out to get to the heater. Actually it wasn't that bad, took about 4 hours. It was the foam has disintegrated on the flaps in the heater, took longer to clean the poxy glue and backing off the flaps than take the dash out. I think this fault is well documented on here. Once done the heater is toastie now. One tip though, where the plastic heater air casing mates up to the dash air ducts, sort of a square shape, over the years this must have got warped as I had at least a 5mm gap at the bottom and one side and no amount of tweaking could get them to seal, this would have meant all the air would have blown out behind the dash. I sealed it with some air con duct tap we use at work. Hope you can get yours sorted with out resorting to this. Cheers David

25-02-18, 07:36 PM	#7
msh 4 ring whore! Join Date: Jun 2008 Location: Rucava, Latvija Posts: 3,816	The cause could be just as well coming from foam in which heater flaps are covered, being totally disintegrated due to age, leaving bare metal with big holes and allowing at least half of air bypass matrix even when set to full hot. It could be caused by age alone, and if there was heater matrix failure in past, without flaps being recovered at the same time as heater matrix change, there would be failed flaps as well, accelerated by hot steam. So, if you remove heater from the car and see that central flap [the one which do or doesn't block panel front outlets] is bare, prepare to split the heater and re-cover the flaps. Some use duct tape, but more proper material is drywall amortisation tape, widest one, comes in big roll, can be bought in construction stores, and that roll is enough for at least 20 heaters... As for aftermarket heater matrixes - care must be taken, as there are some "souther" variety matrixes, with low count of ribs, resulting in low heat output. I for this reason have two heater matrixes to compare - crappy audi B series one and OEM mk2 golf one [identical, apart from outlet angle] - the difference between the two is quite noticeable.