Massive Coolant Leak near firewall - AudiWorld Forums

Go Back   AudiWorld Forums > Audi Models > Audi A6 / S6 / RS 6 > A6 / S6 (C5 Platform) Discussion
Sign in using an external account
Register Forgot Password?


A6 / S6 (C5 Platform) Discussion Discussion forum for the C5 Audi A6 and S6 produced from 1998-2004

Massive Coolant Leak near firewall

Reply
 
 
 
 
LinkBack Thread Tools Search this Thread
Old 08-12-2011, 01:47 PM   #1
AudiWorld Newcomer
 
Join Date: Aug 2011
Posts: 5
Default Massive Coolant Leak near firewall

I just recently replaced my water pumpback in May due to I had massive amounts of water and coolant leaking from my car. The heads were checked and nothing was warped. The leak stopped for about a month and a half and now the problem is back again. This time, the reservoir will not even hold water at all. With the car completely off, I put the water in the reservoir and whithin a minute, all the water has leaked out. I took it to a master mechanic and he said the water is coming from the back of the block near the heater hose to the firewall. I had all the hoses checked for the radiator, coolant lines and heater hoses. No tears or leaks. He is a master mechanic and does not regularly work on Audi's. He could not tell me what the part was called, so I am inclined to take whatever he says as BS. What could this be? I have been reading a lot about auxillary water pumps, j plugs, and compression rings. Someone please help!
jensen_jenniferl is offline   Reply With Quote
Old 08-12-2011, 01:51 PM   #2
AudiWorld Senior Member
 
tester123's Avatar
 
Join Date: Oct 2009
Posts: 627
Default

Quote:
he said the water is coming from the back of the block near the heater hose to the firewall
Can you visually locate where the water leak is?

Also, What model/year?
__________________
ʘ˥ Pearl White А6 Ч.2ℓ Quattro
Sport, cold, everything -Nav.
▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫
No more OIL or COOLANT leaks! │ T-Belt, Water pump & Valve Covers DONE! │ Trans & F.M.R -Diff Fluids, flangeshaft seal DONE! │ RL Caliper replaced │ CCV replaced with OEM -no quacks! | Both Front wheel bearings replaced│
Fuel Banks 1 & 2 Lean issue fixed (finally!)
Rebuild Bosch 150 Amp Alternator (save major $$$)

Last edited by tester123; 08-12-2011 at 01:54 PM.
tester123 is offline   Reply With Quote
Old 08-12-2011, 01:53 PM   #3
AudiWorld Newcomer
 
Join Date: Aug 2011
Posts: 5
Default

2001 Audi A6 Quattro 2.7T
jensen_jenniferl is offline   Reply With Quote
Old 08-12-2011, 01:58 PM   #4
AudiWorld Newcomer
 
Join Date: Aug 2011
Posts: 5
Default

[QUOTE=tester123;24182744]Can you visually locate where the water leak is?

The mechanic said he could visually see where the water was coming from the end of the heater hose off the back of the block to the firewall. He also had my car torn apart though.
jensen_jenniferl is offline   Reply With Quote
Old 08-12-2011, 03:02 PM   #5
AudiWorld Senior Member
 
Join Date: Dec 2010
Posts: 773
Default

Probably the black cross pipe on the back of the engine that goes between the two heads. Sealed with O rings on either end. One is probably leaking and badly by the sounds of it. $.25 O ring, but absolute PITA to get to.
__________________
'99 A4 2.8 Tip Quattro(220k miles and still going strong)
'03 Allroad 2.7t Tip (Gen I with OE style front, Bilstein rear)
5v/cyl is offline   Reply With Quote
Old 08-12-2011, 06:08 PM   #6
Tech Guru
 
4Driver4's Avatar
 
Join Date: Oct 2002
Posts: 33,259
Default

If it's a massive leak, why is it so difficult to find?
Given that we can only guess, my guess is aux water pump.
__________________
4Driver4

Growing old is mandatory; growing up is optional.

2005 A6 Sedan Q 3.2 (wife's whip)
2003 S8 (Q Ship)
2000 A4 Avant Q 2.8 (daily driver)
1999 BMW M Coupe (clownshoe)
1980 VW Scirocco (mid-life crisis car)
1983 Mazda RX-7 (revolutionary sports car)
1999 Mazda Miata SSB (track beotch, no plate)
2003 GMC Yukon Denali XL (the anti-earth)
2004 Dodge Dakota (hey, at least it's stick and 4x4)
4Driver4 is offline   Reply With Quote
Old 08-13-2011, 12:12 PM   #7
AudiWorld Senior Member
 
Join Date: Feb 2009
Posts: 1,110
Default

Have you checked the rubber hose going from the resevoir to the coolant line in the back of the heads? This hose has braiding over it and that could make it difficult to spot a leak. What about the resevoir itself, as they are known to crack?

Like 4D4 said, if it's that big, it should be pretty easy to locate. I'd unscrew the resevoir, flip it over, look at it, and look at the hoses going to the back of the engine. Then I'd look at the coolant pipe to the back of the heads.

But as 4D4 said, since we can only guess...it could be almost anything.
jseklund is offline   Reply With Quote
Old 08-13-2011, 09:27 PM   #8
AudiWorld Senior Member
 
tester123's Avatar
 
Join Date: Oct 2009
Posts: 627
Default

Just from the common sense angle, my thoughts are leading towards an obvious ruptured hose/fitting. Having said that, it can be difficult at times to find out exact origins of the leak. It is somewhat difficult to find a small leak but, if you are emptying out the tank quickly, things should not be that difficult to trace it. Trace the coolant hoses / route through the diagram and isolate the area. I know, sounds easy typing behind a screen but, that's what really going to help. It's not easy for any of us to pinpoint the leak over the forums as you can understand. Hope you find it quickly.
__________________
ʘ˥ Pearl White А6 Ч.2ℓ Quattro
Sport, cold, everything -Nav.
▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫▫
No more OIL or COOLANT leaks! │ T-Belt, Water pump & Valve Covers DONE! │ Trans & F.M.R -Diff Fluids, flangeshaft seal DONE! │ RL Caliper replaced │ CCV replaced with OEM -no quacks! | Both Front wheel bearings replaced│
Fuel Banks 1 & 2 Lean issue fixed (finally!)
Rebuild Bosch 150 Amp Alternator (save major $$$)
tester123 is offline   Reply With Quote
Old 08-14-2011, 02:04 AM   #9
AudiWorld Member
 
bigdadi's Avatar
 
Join Date: Sep 2010
Location: Boston, MA USA
Posts: 369
Default

Put some colorful or something flourecant can be identified by ultra violet light.
__________________

12 A4 2.0T Quat(In 4/25/12)
02 A6 Avant 3.0 Quat(Out 4/24/12)
07 Outback 2.5i Ltd(Sold 5/4/12)
bigdadi is offline   Reply With Quote
Old 08-14-2011, 04:34 PM   #10
AudiWorld Super User
 
SloopJohnB@mac.com's Avatar
 
Join Date: Oct 2002
Location: Olney, MD
Posts: 6,180
Default

Yeah..that's the ticket with a massive coolant dump...Not.

Just find the ruptured hose or loose/broken fitting.
SloopJohnB@mac.com is offline   Reply With Quote
Old 08-19-2011, 11:05 AM   #11
AudiWorld Newcomer
 
Join Date: Aug 2011
Posts: 5
Default

So I finally got the diagnostics back on my car. It is the auxiliary water pump. Apparantly the not so bright mechanic I took it to before, did not do a high powered flush on my cooling system before replacing the primary water pump. I talked to Audi, ANY mechanic should know to do this when replacing the water pump because of excess debris that gets lodged in the hoses. This is not just with Audi's or foreign cars. This should be done on any car, any time the water pump goes out and needs to be replaced. And apparantly the primary water pump just flushed all the debris back to my auxiliary water pump. I wanted to post this so maybe I can save someone else from having to pay another $800 plus parts to replace it. I would double check the mechanic and ask him what his process will be in when doing the labor. Make sure he recites back to you that he is going to do a high powered flush. Well I know for next time and hope this helps someone else out.
jensen_jenniferl is offline   Reply With Quote
Old 08-19-2011, 11:08 AM   #12
AudiWorld Newcomer
 
Join Date: Aug 2011
Posts: 5
Default

How hard would it be to replace the auxiliary water pump on my own? From my understanding the aux water pump sits underneath the intake manifold. Any special tools needed to do these repairs? Anyone have any site suggestions where I could possibly locate do it yourself instructions that include diagrams????
jensen_jenniferl is offline   Reply With Quote
Old 08-19-2011, 11:56 AM   #13
Tech Guru
 
4Driver4's Avatar
 
Join Date: Oct 2002
Posts: 33,259
Default

Quote:
Originally Posted by jensen_jenniferl View Post
Apparantly the not so bright mechanic I took it to before, did not do a high powered flush on my cooling system before replacing the primary water pump.
I think you're being too hard on the mechanic. The aux coolant pump has been a failure point for years. Blaming it on your mechanic is a real stretch.
__________________
4Driver4

Growing old is mandatory; growing up is optional.

2005 A6 Sedan Q 3.2 (wife's whip)
2003 S8 (Q Ship)
2000 A4 Avant Q 2.8 (daily driver)
1999 BMW M Coupe (clownshoe)
1980 VW Scirocco (mid-life crisis car)
1983 Mazda RX-7 (revolutionary sports car)
1999 Mazda Miata SSB (track beotch, no plate)
2003 GMC Yukon Denali XL (the anti-earth)
2004 Dodge Dakota (hey, at least it's stick and 4x4)
4Driver4 is offline   Reply With Quote
Old 08-19-2011, 11:57 AM   #14
Tech Guru
 
4Driver4's Avatar
 
Join Date: Oct 2002
Posts: 33,259
Default

Quote:
Originally Posted by jensen_jenniferl View Post
How hard would it be to replace the auxiliary water pump on my own?
Very. It's under the intake manifold. That's why the leak was hard to find.
__________________
4Driver4

Growing old is mandatory; growing up is optional.

2005 A6 Sedan Q 3.2 (wife's whip)
2003 S8 (Q Ship)
2000 A4 Avant Q 2.8 (daily driver)
1999 BMW M Coupe (clownshoe)
1980 VW Scirocco (mid-life crisis car)
1983 Mazda RX-7 (revolutionary sports car)
1999 Mazda Miata SSB (track beotch, no plate)
2003 GMC Yukon Denali XL (the anti-earth)
2004 Dodge Dakota (hey, at least it's stick and 4x4)
4Driver4 is offline   Reply With Quote
Old 08-19-2011, 01:02 PM   #15
AudiWorld Super User
 
SloopJohnB@mac.com's Avatar
 
Join Date: Oct 2002
Location: Olney, MD
Posts: 6,180
Default

I agree. Replacing a primary water pump during scheduled maintenance does not require a high pressure flush. Only if you have reason to believe there is crap in the primary water pump cavity.

And yes, I read the blauparts tech article...some truth to it, but if the aux water pump wasn't failed when you did the water pump and there was no reason to believe crap was in there the flush wouldn't be necessary.

Last edited by SloopJohnB@mac.com; 08-20-2011 at 02:20 PM.
SloopJohnB@mac.com is offline   Reply With Quote
Old 08-20-2011, 12:17 PM   #16
AudiWorld Senior Member
 
Airbag's Avatar
 
Join Date: Oct 2006
Location: In my Garage
Posts: 1,425
Default

wait isnt there a big coolant plate or some type of manifold on the back of the engine that coolant goes through and some have been known to corode right through ? thought i saw a thread on this last year .. the guy showed a pic and it showed a giant maanifold plate or something like that coroded right through and coolant was dumping out everywhere.
Airbag is offline   Reply With Quote
Old 08-20-2011, 02:22 PM   #17
AudiWorld Super User
 
SloopJohnB@mac.com's Avatar
 
Join Date: Oct 2002
Location: Olney, MD
Posts: 6,180
Default

IIRC it was the rear main bearing mounting plate....strange failure. But corrosion in aluminum engines can take place in strange places...pays to change coolant every few years.
SloopJohnB@mac.com is offline   Reply With Quote
Old 08-20-2011, 04:44 PM   #18
AudiWorld Senior Member
 
Airbag's Avatar
 
Join Date: Oct 2006
Location: In my Garage
Posts: 1,425
Default

Yes John that is exactly what it was I am thinking we have the same thing here if it is coming out that fast ..
Airbag is offline   Reply With Quote
Old 08-21-2011, 05:48 PM   #19
AudiWorld Member
 
Join Date: Dec 2002
Posts: 250
Default

To clarify 4Driver4's reply, replacement of the aux pump has a lot of steps and requires lots of patience, organization, and good labeling. There's a lot of disconnecting to get at the pump. But it progresses; it's not a fight-one-thing PITA, like my current favorite, the front suspension (pinch bolt). It also doesn't require specialty tools, like timing belt. But you'll be disconnecting several dozen hoses, pipes, and connectors and removing the intake manifold. Start early in the weekend.
rocketman4321 is offline   Reply With Quote
Old 08-21-2011, 05:48 PM
AudiWorld
Audi R8




Paid Advertisement
 
 
 
Reply

Tags
2001, audi, auxiliary, coolant, fire, firewall, leak, leaking, loss, massive, pump, s4, tacoma, wall, water

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -8. The time now is 10:23 AM.


Copyright 2014 AudiWorld.com Audi Enthusiast Community