Instruct: Classify a given Amazon review as either positive or negative.
Query: It actually works

I was afraid that I had a blown head gasket because I'm losing antifreeze. Purchased this kit and used it according to the directions. NO LEAK, thank heavens. To double check, I took the setup back to the exhaust and with the first suck of exhaust the fluid changed color. Now at least I know what it isn't! Plenty of fluid comes with the kit to do many tests.