hewtown

2001 A6 2.1T APB

I've had a slow coolant leak for quite a while. I figured the culprit was the aux coolant pump based on inquiries in this forum. Of course I put off doing anything about it, as all I had to do was add 1/2 liter of coolant maybe once per month over the winter. I know, stupid to ignore the problem like that.

Which brings me to today...low coolant warning, and for the first time my coolant temp gauge is about 3/4 (it had always stayed at mid). So I get home, stop the car, and I filled up with a 1/2 liter like usual. Only this time the levels in the reservoir didn't stabilize. So I keep adding, and keep adding, and keep adding....5 liters all together (6 liter capacity in my car). Then I notice coolant just POURING out the underside of the car, pretty much in the center of the engine (my underside guard cover thing is off btw). WTF this isn't good.

So finally the pouring stops, but the coolant reservoir still shows low. I start the car (car is totally cool by this time), leave in idle, and coolant starts leaking again in a steady stream. Double WTF this isn't good...

All this time the aux pump isn't running. So questions are, what is going on? Where is the leak? Is it the aux pump just finally blown wide open? Or maybe a leaky connector unrelated to the aux pump somewhere that was the slow leak the whole time, and now it's blown wide open?

Other question is what are the dangers of driving hot, or with low coolant? I ask because I'm poor as dirt, and opportunity to get the car into the shop won't come for awhile.

Any help guys? And sorry I'm a relative newb and total dumbass for letting this get this far...thx in advance.

Prospeeder

the hoses for the Aux pump notoriously burst. Replace them when doing the pump.

hewtown

Thx...like I said, the coolant seemed to be leaking from the center of the engine more or less. I have the A6 Service Manual, and it looks like the Aux Pump is located centrally, but I can't tell for sure due to my newbness...does everything still sound like the Aux Pump is the problem?

Headed now to take off the engine covers and see what I can see.

Prospeeder

Yes it does see thats the issue. You will just need to remove the intake manifold to access it. If you look in and the valley is filled with coolant, thats it.

2.7Lturbo

aux pump, without a doubt! dont worry about the overheating, as long as you fix it before you drive again you should be fine

let this be a lesson, dont put off fixing parts of the car that can lead to a critical failure. oil/cooling systems are critical to the operation of these motors, if the coolant fails, you have little time before the oil overheats, if the oil then fails, your screwed.

hewtown

Well I can't go so far as to remove the manifold (or so much as the Y pipe) at this time, but I'm pretty sure it is the aux pump. After removing engine covers I can shine a flashlight and see coolant pooling in the area of the manifold.

Any assurance that the aux pump is the proper diagnosis would be greatly appreciated. I'm planning to order parts very soon.

Also, if someone could provide warnings (or tips even??) about living on the edge of overheating that would be great. I just don't have a lot of options til this weekend. If I could just drive a couple miles tomorrow and Friday it would get me to this weekend when I can do the job. Yeah, I know this paragraph is ridiculous, what kind of idiot drives his car on the edge of overheating??? Many apologies to the Audi veterans out there...

2.7Lturbo

DONT DO IT, seriously, its an all aluminum engine, you can break alot of things, not to mention if your oil overheats you can damage your turbos (coking).

its never worth it, i trid to limp around my old volkwagen, ended up badly warping the head.

just dont do it. for the sake of your audi, a 100 dollar pump repair could end up a lot more costly if you do :/

hewtown

Thanks for the wise words...and this pretty much answers my question about "living on the edge of overheating". Again, my apologies to veteran Audists, and to my engine in particular!

So I will follow Truewit's beautiful tech article on the job this weekend. Planning to order parts shortly...I've found the pump and manifold gaskets here on my initial search: http://uspmotorsports.com/product_in...roducts_id=583

Any recommendations on parts and where to order from would be appreciated!

hewtown

Advice will be heeded!!! Thanks again!

And $100 pump repair? Where can I find it for $100?!? $140 is the best I've found so far.

Edit: Found non-OEM for $109 on World Impex. Is this advisable? Also, they sell the gaskets, but I can't tell if quantity on 1 actually means the 2 gaskets required. What do you think?

2.7Lturbo

http://www.ecstuning.com/Audi-C5_A6-...r_Pump/ES2710/

oem part, 107$