My daughter's car had a small leak, which we believe originated in the air conditioning unit. After two days of diligence in trying to discover the source, Marc's was unable to do so. It may have to do with the freezing temperatures. However....they didn't charge my daughter a dime because in their words, they didn't do anything. I was disappointed the leak wasn't found, but happily impressed they didn't charge a young lady anything (even though they had a lot of time invested in the search). I'm confident that the leak will be found in the spring. Marc's is a business with integrity and I highly recommend them!