I have a pretty fast coolant leak but i cant find it and its driving me crazy. I've parked the car and watched for drips, put something under it and checked later, and i cannot pinpoint where the leak is. I've seen producs that you're supposed to add to the coolant system which "finds the leaks" and plugs them (so i guess it gunks them up). Is this stuff safe? For the life of me i cant find this leak, and its fast, i can fill er up and the light'll be back on in a day. Any suggestions? THANKS!