Not sure which 2004 Ford Mustang Performance Monitors are right for you? We have over 2412 customer reviews, with an average rating of 4.5, to help you find exactly what you're looking for. Jason F from Huntsville, AL said, "Enjoy being able to monitor trans and coolant temperature as well as real time ignition timing. I'm still trying to get "distance to empty" calibrated. Overall this is a great "monitoring" tool."