I tried the Consumer Reports recipe posted by Dale B a few days ago, with mixed results.<p>The recipe was essentially this:<p>1/2 cup Sudsy Ammonia <br>16 ounces 70% isopropyl alcohol<br>1 teaspoon dish detergent<br>and enough distilled water to fill a gallon jug.<p>I decided to whip up a batch (after letting the reservior run dry on my car). This stuff might be suitable for cleaning windows, but it is not nearly strong enough for Washer Fluid.<p>Before I even put it in my car, I decided right away that 16 oz. of alcohol was not going to be enough, so I doubled it to 32. (Since I bought a couple dozen 16oz. bottles for 25 cents apiece at the Super KMart, I wasn't too worried about it). I also skipped the dish detergent, since the ammonia already made the mix somewhat sudsy, and I was concerned about the mix getting too foamy.<p>As it turns out, even that wasn't enough. After I filled the reservior, I could tell that it still wasn't strong enough. I could not smell the alcohol at all, the the fluid was freezing on my wiper blades and windshield.<p>So I added a third 16oz. bottle, which was better (It no longer froze on my Windshield), and then finally a fourth, which brought it up about to the level of the factory fluid (at least to my nose). I may even add a fifth bottle of alcohol to give it a little more kick. Some more ammonia would probably make it work better as well, but I personally dislike the smell of ammonia (I don't mind the alcohol odor, though).<p>So here is my recipe as it currently stands.<p>1/2 cup Sudsy Ammonia (more if you can stand the smell)<br>64 oz. 70% Isopropyl Alcohol<br>enough distilled water to fill a gallon jug<p>Tom Halter<br>98.5 2.8 QM Pearl/Onyx

nt<br>

(nt)

But wasn't offered as a replacement for good old windshield washer fluid. Soap and ammonia will lift your wax - not an issue when you're cleaning the vinyl fog off the INSIDE of your windows.<p>Mr. Squeegie

And like another poster noted before, don't use it inside if you have had tint applied.<p>As for the revised recipe, that looks like WAY too much isopropyl alcohol (fully half of the mix is alcohol). It might be effective in cleaning, but I'm not sure what the point is here. I would just buy the freeze-resistant commercial stuff, or even better go to Audi and they should refil you with the original under Audi Advantage if you are still in the warranty period. (Although it is possible that some dealers will refill with something else).<p>The original CR recipe was developed as something that works better than commercial products and is cheap and easy to make. I'm sure they played with the formula some to get it right.