samm

I am going to be replacing the heater core on my 92. I am not looking foreward to this job, it looks like a pain in the ***. Anyone have any tips to save time, headache?

Thanks.

A6Gary

Two Tylenol, and lots of time and patience. Good luck!

duglmac

But if you must do it yourself, the tylenol will help, and maybe a massage. It is do-able, but it is not for the meek.

(note: the following is based on my experience doing this, use your own judgement when doing it yourself)

I just did it on my '98 A4, and plan to do it on my '96 A6 wagon if it goes. I am not a professional mechanic, and I had never done it before. It took me 10 hours (not all at once) to get at the core. 10 seconds to replace the core. Then about 5 hours to put the car back together again. It's not really difficult, just tedius, and much is done on your back with your feet up in the air.

I used a non-audi guidebook. Some of the directions are 'remove the so-and-so' and don't say how, or 'remove the red connector' and there is no red connector. So if you're not ready for that, you may want to re-consider the project.

When you get to the core, the entire front of the cabin will be dissasembled to the firewall, so don't let your wife/S.O. see it or they will freak out. The corallary is, if you want to freak out your wife/S.O., then invite them to take a look

As far as tips go, I found it usefull to keep a marking pen and some white electrical tape handy to mark each and every wiring connector when you disconnect it. It would suck if you finish re-assembling, and the car doesn't start because the red wire that goes from the clutch pedal switch to central locking is routed through the insrument cluster harness connector that you forgot to re-connect.

It is tempting to cut corners. You will not get the core out without removing everything in front of it(.)

The only things going through the firewall are the A/C and the radiator to the heater core. They must both be disconnected. There are fines for knowingly releasing coolant into the atmosphere, so I had my A/C discharged before I started by a certified tech. Consider the re-charging of the A/C afterwards as well.

good luck, and post an update during/ after.

Just a repeat: use your own judgement, this is only a discussion based on my experience doing this, not an official guide.

ciao
Doug

arthuraudi

I haven't done a core replacement on an my Audi yet. But I did have to replace the core on my VW Fox when I upgraded it to have A/C (Don't be shock its Fox without a/c). I spend a LOT of time and I could not use the car. You should label your conections, keep your screws/nuts in several containers, if u can take pictures and once u start keep onlookers away from your project as they would attempt to discourage you. Be prepared to lay on your back for extended periods of time. But its possible!!! There is very good information at this address...<ul><li><a href="http://www.alldata.com">http://www.alldata.com</a</li></ul>

beep-beep

You can do it from the plenum chamber.
You will need to:

- disconect foot air ducks
- drain coolant
- remove chamber cover and the wiper assambly.
- disconect all vacule tubes, wires and coolant pipes from the fresh air box. Box hold in place by the metal strip - remove it.
- remove a rubber air hose.
- pull the air box out. This is hard part. It sits on the sticky insulation and migh be hold by different stuff. Be sure to not brake a AC pipes.
- replace the core (I am not sure about this part )
- reasambe in the reverse order.
- fill coolant.
- run engine for some time with heat on
- add coolant.

samm

Thanks everyone for the tips. I will let you know how things go. I don't see why the AC would need to be discharged to replace the heater core. Is the AC not in a seperate box connected only by a large bellows?

duglmac

Maybe it is different in th older models.

This was a '98 A4, and everything had to come out because the heater box and cooler box were all attached behind a crossbar.

beep-beep

do not listen to them - listen to me

samm

Gotcha. mine is a 92 100 wagon, two seperate boxes. Thanks for the clarification.

samm

Thanks for the info, sounds like you are on track with this procedure. Do I have to disconnect the wires from the servo motors before I remove the "black box", or can I pull the box up a little and get enough room to DC the wires from there?

How much of the dash/console do I have to remove if any, or are the footwell ducts the only thing I need to remove on the inside?

Thanks,
Sam