I tried searching for topics on fuel/engine additives but didn't come up with anything so here's my post. I mentioned to a mechanic at firestone that I used a Gas treatment and Fuel Injection cleaner additive in my car. He told me that was the worst thing I could do because those are made up of mostly water. Basically, I'm asking can anyone shed some light on wether fuel additives are ok for the car or not? I checked bobistheoilguy.com and read some interesting stuff on oil additives and i'll never be using a oil additive for sure. But i'm curious on the fuel additives. Thanks.