Stranded with massive coolant leak - 2.7T allroad

[kermac]

I recently bought a 2001 allroad with 2.7T motor and 6-speed dual-range gearbox. It has done just 80,000km or 50,000 miles.

I had the ecu flashed with a GIAC St I tune last week.

I noticed a slight smell of coolant after a trip a couple of days ago. Today the weather was much warmer (almost 30C or 85F) and after a short run I parked the car. I returned to find a fair-sized pool (perhaps a pint or two) of liquid seeping out under the RH front door. I drove to a mechanic (maybe 5 miles), and just before I got there the low coolant light came on.

As soon as I parked and switched off, fluid could be seen running under the car. The engine was bubbling and steaming a little. The coolant reservoir was empty and we added liquid (water only at this stage) which came straight out the bottom of the car. When we got the undertray off, most of the fluid seemed to be falling roughly under the LH headlamp - ie at the front LH of the engine. The mechanic couldn't see much (it IS an Audi...) and couldn't locate the main leak at all but he thought he saw some fluid leaking at the back of the engine near the heater hoses. There was a relatively small amount falling below the RH rear of the engine.

From the location of the fluid leakage described above, does this sound consistent with auxiliary/secondary water pump failure? Is it possible there could be a simultaneous failure of the plastic heater hose T-piece?

I know this has been regularly written up, but wanted to narrow down the possibilities before planning my response.

Thanks all

[Taichi07]

The same thing just happened a day ago to my C5 as well...dumped all coolant in under 30 seconds. I don't have a fix yet and I am getting very nervous.

[ChrisEsco1]

Sounds exactly like my ordeal. Ended up being the t-stat. Replaced the plastic water pump with a metal one at the same time.

[A6Avant]

Sounds exactly like my ordeal. Ended up being the t-stat. Replaced the plastic water pump with a metal one at the same time.

Dido...

[Asicks]

You may want to get a new tstat housing. The plastic tstat housings are prone to cracking at the the tstat seal.

Pickup an aluminum housing if you can.

[ENDEE666]

You need to establish where more specific. As far as possibilities - Tstat, Water Pump, Upper/Lower Rad Hoses, Radiator, Aux Pump, Various Hoses... So there is a lot of possibilities.

If it does originate at/near the headlight, I would lean towards rad hose. Either look closely for the leak point when it firsts starts spilling or get the UV Dye and find it that way.

[Vinchenzo51]

Dido...

Ditto*