RickM

My wife just called and said she got a "low coolant" light on her dash. Is there a special coolant she needs to use? I'm not anywhere near home, and don't have access to the user manual.

muhammadc

FWIW, the coolant in my A6 is green, but the coolant in my 100CS (recently flushed) is red (I *think*)... the water/antifreeze mixture is 50/50.

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Audi Official Factory Repair Manual: Cooling system, draining and filling

Note:

<i>Prominent designations for coolant additives are G 011 A8B or C. There are coolant additives that correspond to the TLVW, but are not released by VW/Audi. Only coolant additives with the designation G 011 A8B or C can be used.

The cooling system is filled year round with a mixture of water and G 011 A8B anti-freeze.

G 011 A8B prevents freezing, corrosion damage and scale formation and raises the coolant boiling point. For these reasons the cooling system should be filled with G 011 A8B anti-freeze and anti-corrosion additive all the year round.</i>
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I'd get the coolant from an Audi dealer or repair shop. I'm not exactly sure if it's any different than antifreeze you can find elsewhere, but you might have the red coolant... I am pretty sure my 100CS has that (can't check right now). Just as long as you're adding what is already in there, and not the wrong type.

I'd have the cooling system and expansion tank cap pressure tested for leaks, if the level is low enough to kick off the warning light.

Richard Solomon

Then check the system and adjust with G12 (special VW/Audi only coolant).

G12 is pink and coolant reservoir should have big note with book icon and G12 on it.

In any case, adding 8oz of water should get the light off and let her drive it for a while. If it take a lot more water, or the light goes off and then comes back on, she's got a big (leak) problem and should probably not drive it

HTH,

Style12v

If you have the red coolant in there, you can ONLY use more red coolant. Mixing will cause engine damage and problems.

If you have any other kinds, you need any phosphate free coolant.

my best bet would be to add some water for now and drive to the dealer and get some more of the kind you have.

Richard Solomon

Muhammad would know...G11 likely then. BTW, DON'T MIX G12/G11 with any other antifreeze!!!!

AeroSmith

Don't use anything but the red Audi coolant or water (preferably distilled). Using other coolants can cause the coolant to turn to jello.

Josh

captainbilly

If you use any long life antifreeze you will be fine. There are only two basic formulations of antifreeze; ethylene glycol and propylene glycol. Normal antifreeze is ethylene glycol while the environmentally friendly kind is propylene glycol. The difference in the long life kind vs the regular kind is in the corosion inhibitors, lubricants, etc. and not in the base which is ethylene gloycol in both cases.

All of these are mixable in any proportions but there is no advantage to adding a propylene glycol based antifreeze (environmentally friendly, non-toxic) to ethylene glycol base since the non-toxic nature of the propylene glycol is negated.

muhammadc

Yeah, that can be repeated... don't mix them!!

Kenny

Tap water has chlorine and other solvents which corrode your coolant system and eats through water pumps...

A low coolant sign can be a variety of problems.. A bad sensor, a loose hose, leaking water pump, cracked radiator, bad thermostat or worse case scenario, head gasket leak...