Am I DOA? Driving with coolant warning

A6 All/ S6 All
#1

I had to drive about 10min with the low coolant light on (city traffic). During that time, the engine temp gauge stayed at 1/2 and did not rise.

I think it was a coolant leak at pressure, I saw steam coming out on the passenger side, and it smelled like coolant. The next morning I poured about 1.5L of G13 in the expansion tank and the level remained steady while the engine is off.

Today, I finally had a chance to take it to the nearest garage (Courbevoie outside of Paris). The engine seemed to emit steam after 2m–before the temp gauge even reached 1/4. It was coming from below cyl2/3, from the gap by the passenger air filter.

I was hoping that the leak was from a hose or clamp that popped loose from heavy, cobblestone-induced vibration (an ill-advised Eiffel Tower joyride). But the (non-Audi) garage mechanic said they spent 3h searching for the leak and couldn’t find it.

Now it seems to me a pressurized coolant leak should be easy to find, right? But they said it seemed to be engine exhaust, not coolant. (Of course, I don’t speak French, and my friend translating doesn’t speak car.)

Is there any way that I could have warped an engine block/seal/gasket by driving it on low coolant when the engine temp gauge does not move? Am I DOA, or should I find an Audi mechanic who speaks English?

(There is so much more to this crazy story, but I’ll leave it for another time. However, this is a real pain cause I’m 300km from home and there is nowhere to park a disabled car in Paris…)

#2

If your coolant temperature gauge is not going up, I would just top off the reservoir and monitor.

#3

Unfortunately, there is still an active leak. Steam/smoke coming out the front passenger side after a few minutes of driving.

#4

Has the alternator ever been removed?

#5

Generally if the gauge stays in the 1/2 spot you’re okish… The actual temp gauge won’t move past that half part even if the car is over heating. Did you ever replace your coolant T fitting coming off of the coolant tank?

#6

Yes. The T fitting was replaced. The steam was coming from the area below cyl 2/3. I had video, but then my phone was stolen later that day. :sob:

I should also add there was no CEL. The alternator was never removed. But the hoses to the radiator on both sides were replaced 2y ago.

#7

Oh my gosh… That’s not good. If you can take a few rags and zip tie them in a few areas AWAY from the exhaust but located in the spots under / Next to and behind the coolant tank following the coolant lines. Drive and inspect the rags. The rags can help tell you if there is or isn’t pressurized coolant leaks in that area. The coolant could be coming from the alt or oil cooler area. But doing the rag test should help at the least start elimination of issue areas.

1 Like
#8

The alternator would have been removed when the oil cooler orings were done two years ago.

https://forums.audirevolution.net/t/help-me-find-the-source-of-this-oil-leak/16393/43?u=eng92

#9

I spoke with the mechanics and they were certain the coolant hoses were all intact. They said the leak is coming from an engine seal, but they could not pinpoint the location.

So the alternator or oil cooler could be a good guess. Unfortunately, I can’t seem to find an independent Audi specialist in Paris and the dealers won’t work on a US spec car…

#10

I kinda have the same issue as you have. Engines not overheating or anything I just need to top off the coolant every couple of months however what I found was that the reservoir has a hair crack. Everytime I step on the gas and floor it and the pressure rises I’ve seen some pinkish drips coming off of the reservoir and it was very wet around the bottom of it. You can only see it when the air filter box is removed otherwise it is impossible to see it. It’s actually fairly common for the coolant reservoir to develop cracks because let’s be honest it’s a plastic tank around a very very hot engine and these cars are all at least 11 years old now.

Is there oil inside your coolant reservoir?

#11

Plus the coolant then drops around the exhaust manifold which might explain the smoke.

#12

the coolant reservoir is clean. I also removed the air filter and ran the engine a bit at the onset of the problem, and it was not a leak that dripped along the hoses to the manifold. the hoses all seemed dry. the steam seemed to come from further below. I had video, but it was on my (stolen) phone.

The good news is that I found a shop that is familiar with the v10 about 40m away from my place. And I managed to schedule a vehicle transport pickup for Monday at 9am. The bad news is that the driver side rear window is already smashed––however, no other damage. 2 more nights…

#13

Wow people have become savages now… coolant lines almost never fail unless animals take a huge bite out of them. Try to drive it a bit harder and then try to take a look beneath the reservoir…on mine it was really damp there. But would be strange to see steam coming out of the headgasket. I’m no mechanic at all but wouldn’t this interfere with compression? So maybe misfires around 2 and 3? Really weird.

#14

Finally got the word from the mechanic. Here’s the translation from French

“We checked your car for the water leak. We found a water leak at the oil cooler and alternator hoses. For this repair we must disassemble the entire front of the car.
[…] For the repair of the water leak 1400 euro VAT included.”

As usual, you guys were spot on.

#15

Had a leak in a similar location after replacing my alternator 2 years back.

https://forums.audirevolution.net/t/almost-there-first-start-rough-idle/16659/15