gmakarevich

Ok, I don't believe I did this, but ...

I pulled both heater hoses and replaced them on my 1989 80. However, I didn't mark down which hose goes to which outlet on the firewall.

All I need is one (I think I can figure out the other, hopefully)

Which outlet does the hose that connects to the back of the engine block go to? Right or left when facing the firewall (standing in front of the car).???

Hoping to keep my 1989 80 going until August 2009 (20 years, 258 k miles, original clutch!)

Lago Blue

I think the heater will function in either case.

Does '89 80 mean four cylinder?

Your car has a coolant shut-off valve in the line, correct?

You also have a bleed-screw ("B" in photo) in the line? I've always seen that on the passenger side.

The lines don't cross, the hose from the T-stat on the driver's side of the engine connects to the same side of the heater core.

This photo is a 20V, but perhaps yours is similar.

The factory drawings can be found here:

http://dimon.drummotor.net/techdocs/AudiB3/01/19.pdf

page 3 of 17 shows the four cylinder.

Hope this helps.

gmakarevich

It's a four cylinder, so the diagram on page 3 was correct. That one doesn't make it clear. I called my Audi dealer and they said the one from the block goes on the driver's side. That makes the one connecting to the thermostat on the passenger side.

I would think it doesn't make that much difference, but I will go with what the dealer said.

This set up does not have a bleeder valve. We checked the part numbers on the hoses and they were correct. Neither has the bleeder valve (must be a 5 cylinder feature)

If anyone else wants to chime in, feel free!

I'll post once I get things put back together.

Thanks