Heater Matrix Audi 80 b3 1.8s. Leaking ?
 

:grr:

Every time I go to a show something seems to happen! I went to the classic show at Ripon this weekend and the car decided to steam up (never has it done this before). I know it was raining but could I get the windscreen to clear ? No!
I tried the setting at hot, no luck, cold almost as bad, every thing I tried to keep the screen clear seemed a waste of time.
Got back checked the footwell It seemed a little damp but there again it was now full of wet grass from Ripon racecourse.
Checked under the bonnet for leaves in air intake, a found few. However I have foam blowing from my air vents so I'm starting to think it may be the heater matrix leaking? Has anyone had this problem?
I'm I right to believe it will involve hours of fun removing the dash etc or has anyone else found an easier way of checking for a possible leak in the heating system? Knowing my luck I will spend hours and hours removing the dash to find nothing wrong Any help gratefully received. :wall:

Chances are if your 80 hasn't ever had one, it now needs one purely based on age. Every B3 owner has to do this its almost a rite of passage!!

Yes, its a dash out job. The first time you do it it will take more than a few hours and you will find other bits and pieces to do along the way, heater flaps, wiring abortions and such like. There have been some very good how-to guides written over the years.

You'll know its gone if you are constantly topping up with water, wet footwells, excessive condensation, greasy film on windscreen etc. Foam from the vents - prob a safe bet your flaps at the very least have had it I'd say :o

Find where the lower vents are for the footwell on the passenger side, have a quick feel inside, if its wet there you have confirmed it without taking anything apart. This is where the matrix lives and is its lowest point.

Good luck!

As above, good advice !

yep! have now left car to dry overnight in garage with roof open. Felt the bottom passenger airducts and are now wet with brown bitter tasting water! strange how things suddenly start- Saturday fine and heating working ok and on Sunday heater broken!

Thats how they go, all at once!

I feel your pain, BTDT on several occasions - you are about to embark on at least a weekend of stripping parts, drying carpets and insulation, bloody fingers and reducing your motor to a state it hasn't seen since it was being built! Good learning curve though, its a lot easier the second time round;)

Whilst I'm replacing the matrix, and as foam has been blowing from the air vents; I must presume that the foam has come from the from the heater box vents ? Would that be correct ? and if so any idea of thickness of sticky backed foam required? :yikes:

I had to do this job on my b4 last winter, presumably similar to a b3? It took me all weekend to sort out, but the matrix itself is a cheap part. There is an absolutely brilliant walkthrough created by Paul Goodwin and Ian Simmonds found here: https://www.s2forum.com/articles/200...lacement-guide

I bypassed the matrix for a few weeks until I had time to do it. At least this stopped the carpets getting further soaked.

Or you could pour in some K-Seal. I did this on a B4 six years ago and it's worked exactly as advertised. It's a lot easier!

(Yes, I know its not the ideal solution...)

Thats a great doc for matrix change, I used it to change mine a year ago.
1 little tip, when you refit the lower 2 bolts each side, page 7, 2nd pic down, put duct tape on the carpet you pull back or something to stop you dropping the little bolts down between the carpet and the transmission tunnel, had to take the poxy carpet out as I couldnt retireve the bolt and I didnt want to be beaten by leaveing it in there.

The doc seems very handy indeed I'm sure its very similar to my B3.
Thanks for everyone's help. :tup:
May I ask for anyone's advice who has done this before , as what they consider to be the best Matrix for an Audi B3, any particular brand or more to the point what to avoid (obviously only there opinion) ? and also what thickness of replacement foam is required ? :tup: