If you're looking to buy a new used car, then Eric has a great tip for you to avoid getting scammed— look into the horse's mouth. Yes, that sounds cryptic, but it's a very similar process where you look underneath the oil cap. If it looks smooth like it should, go ahead, think about purchasing that vehicle. But if there's a lot of built-up black gunk on the bottom, do yourself a favor and RUN. That engine is destined for failure.