I have a 1999 Dodge Status with 184K miles on it. I was considering replacing all of my fuel injectors as I had at least two of them barely working and I had rough idling and poor gas mileage (~10 MPG). I witnessed the HEST test and I decided to try the B-12 Chemtool ($4.99 at my local parts store). I put a can of it in my empty tank and then filled to a 1/2 tank with premium. Holy Cow!!! My injectors are all firing 🙂 Yay!