mtroxel

The tube that runs between the out and in on the heater core is a vacuum hose...brings vacuum to that accumulator (big plastic bottle thing), then from there to the vacuum devices on the HVAC box.

Coolant in the box is not normal...not at all. Youve got a leak in the heater core, or a crack in the plastic top of it where the plumbing comes out. You got to get a new one Pete. No way around it.

Pete_A4

is that 100% sure its cracked or is there a way i mixed up the wires or tubes cuz wen i got it there was no coolant inside??

Pete_A4

actually i think its in the hvac box the one that has all the motors and flaps. I cant see how the tubings for the coolant go into the hvac box but doesnt get any coolant inside it itself?

mtroxel

The heater core sticks out through the firewall, and that's where the heater hoses clamp on to it. There are no hoses with coolant in them that connect inside the car so you could not have mixed up anything that would put coolant inside the HVAC box.

All other tubes back there are just vacuum hoses. I attached a diagram.

Pete_A4

thanks alot so how would coolant get into the box? from where would the coolant be coming from?

mtroxel

It's either leaking from the core itself, or the top of it. Look at the top where the tubes come out of it. It's a plastic that get's old and brittle after 14 years of heat/cold cycles. When you took off the heater hoses the stress can be the last straw and you crack it open.

Ask me how I know...........

Pete_A4

but i thought those hoses dnt have coolant flowing thru them?

mtroxel

I'm talking about the two hoses from the engine to the heater core pipes that stick through the firewall. You had to disconnect those to get the heater core out. They carry coolant in and out of the core.

Pete, you need a new heater core. As Audi parts go they aren't expensive. And I would never go through all that work, see coolant in the car, and even think about putting a 14 year old core back in.

Get a heater core.

Kris Hansen

Coolant inside the box = leaking heater core.

Pete_A4

ok i guess i have no choice. still doesnt make sense 2 me but ill take ur expert advice