Check your expansion tank cap. I got a defective one that didn't seal properly and it caused me to lose coolant out the cap. New cap solved that issue. I also got my car back from the dealership yesterday and they didn't bother to tighten the cap all the way down. I lost 3/8ths a gallon with the cap being loose over a 20 mile drive. It left white coolant residue everywhere including on the expansion tank.
Last edited by briangl92; 10-05-2012 at 04:46 PM.