Only G12 is approved for our system. Do you really want to find out if it works fine or not?

 

the new prestone works fine in it... the stuff thats good for any make... Of course if your car blows up its not my fault, I use it...

 

Thanks Jest. I'll try that. The gauge reads engine temp is normal even when warmed up.

Red coolant? green coolant? Well, I have BROWN coolant. Time for a flush. Where is the best place to drain the fluid? Is there a brand of flush that is best?

 

deffinately time to flush... I dont have a preference they the same basicaly folloe the directions and make sure you get it all out ..

 

Open up the coolant expansion tank. then open up the valve on the bottom right side of the radiator (red twist valve I think). Make sure your pan is large enough to hold 2 gallons of coolant. If you like you can flush the system with a garden hose. Just feed water for a few minutes into the coolent expansion tank. Then flush the system out with a gallon or two of distilled water. Close the valve and fill the system with one gallon pentosin G12 and one gallon distilled water (deionized preferably).

Do not mix coolant types, and you really should only use red Pentosin G12 (from audi or bmw). The other brands may work but the audi cooling system isn't designed to work with them.

 

I just bought some flushing solution and green Prestone. Prestone seems to be very opionated about every car manufacturer coming out with their own coolant. The fact is, they all need to do the same thing. Good heat transfer, reduce corosion and low freezing point. Physics is physics. The Germans don't have their own perodic table.

 

You do know that the components in german cars are not made the same as American cars and therefor can be damaged by using green coolant? If your theory was true then why can't you put regular power steering fluid in? Because it will eat through the seals and destroy your steering rack/pump over time. Same thing goes for using green fluid. They don't color code them for the hell of of it.

 

Gregp, Green stuff is not compatable with the aluminum parts and the interior of the system will corrode. Antifreeze consists of more than ethylene glycol and water. If you think you have problems now, wait until you use green stuff in there.

Anyway, back to original issue. I'm not sure how you ended up with brown coolant after 1 month. You said that you filled it with coolant a month ago and now you have brown coolant. One thing that will cause brown coolant is mixing the red and green stuff.
What did you use a month ago?


Drain and flush the system, then put in the correct fluids.

By the way, we never did find out if, when the engine is warm and the heat is on maximum, whether both lines to the heater core are hot. If neither is hot, this sounds like either a blocked valve, or a plugged core.

If they are both nice and hot, the problem is unlikely to be the coolant or core, but rather the valve that directs the air over the heater core.

 

Which is where a VAG-Com would come in handy, to check if the flap motor is operating correctly.

 

I've been reading up on this subject. This Prestone stuff contains nothing that can damage seals or aluminum. Not even German aluminum.

I'm now convinced that, unlike the power steering fluid issue, this falls into the category of the dealer insisting on paying $650 for an ignition control module instead of $150 for an after market one. I'll let you know if my car explodes. (I'm not worried)