Coolant leak - Brake cleaner aint working for me

[Waffles_s4]

Have a coolant leak that am trying to trace. However, with the salt/water all over the place, everything looks like dried coolant right now. I dont see any drips on the bottom plastic pan. Am thinking its the waterpump, OR, a slow leak through the PCV, OR the Intercoolers leaking. However, am not really detecting any coolant in the oil, including a rising oil level as a result, nor any traces of coolant in the oil cap or the oil itself through the dipstick. Intercooler leaking into cylinders? Maybe, but last I did a carbon cleanup, I did not see any traces of coolant, and I dont see misfires at this time.

Used brake cleaner to clean around the waterpump area, hoses, pulleys, etc but its not removing the stains or traces of dried salt/water/whatever it is. When it dries, the tubes, parts, look as if I did not spray anything. Are there alternatives to clean part to their original form without a brake cleaner? [wrench]

[Nillious]

It’s corrosion. You need to use an aluminum wheel cleaner for cast wheels. It will be acidic so the down side of it is it can cause nuts bolt and any bare metal to rust. Make sure you follow up with a good soap and water wash with thorough rinsing. Try to not spray everything in sight. Just the affected areas.

With that said. Audi coolant will usually show up pretty obviously as pinkish residue. You can pull the super charger on these cars in about 15 minutes and look for traces of coolant leaks on the intercoolers.

[SwankPeRFection]

Take the two hoses running to the IC cores in the charger and bridge them together with a T and apply pressure and/or vacuum to them into the charger. If it doesn’t hold the pressure with ZERO change in readying, you have your answer. Doing this is easy and you don’t have to take the supercharger off and the connections are easy to get to and generally you’ll only lose a little bit of coolant in the process. Just be sure to unplug power to the IC aux water pump which you can easily get to in front of the driver side wheel behind the fender liner by removing just three or four screws holding the corner in place and reach in and unplug it. This will keep it from kicking On and spraying coolant everywhere when you unhook the hoses. You don’t even need to take the wheel off to do this.

[Nillious]

If you open the bleeders on the cores and pull the coolant out of the reservoir with a suction pump and transfer it into a clean container you will pretty much lose zero coolant and can reuse it. Pull enough out to get the level below the hoses and nothing will be in the hoses when you remove them.

[Waffles_s4]

Thanks guys.

I think this will confirm if the SuperCharger's ICs are leaking into the cyln, but at that point, I prefer to remove the SC and inspect. I have done it before, its not that complicated to do.

My question though is how do I know for sure if the PCV is leaking slowly into the engine itself?

For the traces, I dont believe its corrosion, just water/salt from the streets (am in Canada, lots of salt in winter), or dried coolant. But it has white residue.

I just need something that can clean these areas but better than brake cleaner, which seems to clean oil residue well, but not what am seeing.

[Nillious]

Water and salt equals corrosion. Take a picture of what you’re seeing and post it up here. People should be able to help you better if they can see what you’re seeing.

[A4Qwattro]

Thanks guys.

I think this will confirm if the SuperCharger's ICs are leaking into the cyln, but at that point, I prefer to remove the SC and inspect. I have done it before, its not that complicated to do.

My question though is how do I know for sure if the PCV is leaking slowly into the engine itself?


Do a pressure test of the coolant system. Also check the oil for coolant (submit sample to blackstone labs or the companies who do oil analysis in Canada).

[Waffles_s4]

Do a pressure test of the coolant system. Also check the oil for coolant (submit sample to blackstone labs or the companies who do oil analysis in Canada).

Did pressure test, did not drop even after 1-2 hours.

I cannot see or smell any traces of coolant in oil. Oil level is also exactly where it is supposed to be, not higher or lower than MAX

[SwankPeRFection]

Did pressure test, did not drop even after 1-2 hours.

I cannot see or smell any traces of coolant in oil. Oil level is also exactly where it is supposed to be, not higher or lower than MAX

Did you pressure test the core loop like I said via the front two hoses? It can be done with the supercharger off if you felt like taking it off.

How much coolant are you losing exactly and over how much time?

[Waffles_s4]

Did you pressure test the core loop like I said via the front two hoses? It can be done with the supercharger off if you felt like taking it off.

How much coolant are you losing exactly and over how much time?

I honestly dont have an idea what u were describing. Also dont have that T you are refering to. Gonna look if there is any Videos I can follow maybe?

[SwankPeRFection]

I honestly dont have an idea what u were describing. Also dont have that T you are refering to. Gonna look if there is any Videos I can follow maybe?

The front of the supercharge where the pulley is. There’s the plastic pipes for the coolant to flow into the IC cores in the manifold. Take two hoses and plug them into the plastic barbs. Then plug them into a T and pull vacuum on the 3rd nipple on the T and see if it holds. That’s the in and out loop for the cores and if they’re leaking, it won’t hold pressure or vac. Either that or cap one nipple off on one of the plastic pipes and the pull vac on the other one. It accomplishes the same feat. That’s why I said you could do this as a test without pulling the charger off. Does it make sense now what I’m describing?

[Krusty]

This is the issue, for sure, wink. Without actually looking at the car this is most common issue.

https://blog.fcpeuro.com/how-to-replace-the-water-pump-and-thermostat-b8-audi-s4

[Waffles_s4]

The front of the supercharge where the pulley is. There’s the plastic pipes for the coolant to flow into the IC cores in the manifold. Take two hoses and plug them into the plastic barbs. Then plug them into a T and pull vacuum on the 3rd nipple on the T and see if it holds. That’s the in and out loop for the cores and if they’re leaking, it won’t hold pressure or vac. Either that or cap one nipple off on one of the plastic pipes and the pull vac on the other one. It accomplishes the same feat. That’s why I said you could do this as a test without pulling the charger off. Does it make sense now what I’m describing?

I do understand what you are refering to. You would like to rule out the SuperCharger's intercoolers. I get it. I did a carbon clean up about 9000 miles ago and I did not see any traces of coolant though. At that point I rather take the Charger off and inspect pretty much everything else: thermostat, ICs, and get a better look at the waterpump.

But none of all that rules out the PCV. Any way to know if the PCV is mixing coolant/oil without taking everything apart?

[Waffles_s4]

I see a bit of coolant missing (say 2-3 cm on the coolant reservoir) every 1000KM or so.

Pretty much all sources related to coolant leak would be involving removing the supercharger itself, but am still not sure if I can inspect or know the PCV is leaking. Was kind of expecting to see some coolant in the oil if that was the case.

[Nelson G]

Buy this: https://www.harborfreight.com/cooling-system-test-and-refill-kit-64985.html?_br_psugg_q=radiator+pressure+test+kits
it wii help you find where the leak is coming from.

[Waffles_s4]

Buy this: https://www.harborfreight.com/cooling-system-test-and-refill-kit-64985.html?_br_psugg_q=radiator+pressure+test+kits
it wii help you find where the leak is coming from.

Have it, used it. Did not drop in pressure, no leaks. Whatever is leaking is probably slow or not directly related to the cooling system? Dunno

Still looking to find something that can clear grease and stains, other than brakde cleaner

[Nillious]

Did you test it hot and cold? Sometimes hoses or gaskets can leak cold but not hot or opposite.

[Waffles_s4]

Only cold, for 2 hours, nothing. I think it was 15 PSI or whatever they recommend.

Could be the PCV, but that would mean it is mixing with oil. Guess the more I drive it, the more it would mix with oil, but then oil level is the same. Confused.

Might take off the super charger and rule out IC, waterpump and thermostat. Dont think there is much else to check.

[sbw]

did you ever find the source of this coolant leak?

[VenturiRS]

Mine was intercooler cores. ~100k
Replaced WP, Thermostat and PCV on the way to that discovery. Guess I'm good for the next 100 now.