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!
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)
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.
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 & Diff Fluid DONE! │ Bearing & Inner Tie-rod Next │ Steering leaks? │ Fuel Banks 1 & 2 Lean issue fixed (finally!) Rebuild Bosch 150 Amp Alternator (save major $$$)
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.
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????
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.
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.
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.