I had a 91 TBI caprice. I started the engine with the air box off. I put about half a can in a spray bottle, and sprayed it down the throttle body till it was gone, while working the throttle to keep it running. After I put the remainder in the tank. It really cleaned the car up, and I saw an increase in miles between tank fulls.
It will smoke and cough like crazy while you are doing it, just keep the rpms up enough to keep it running.
2014 Chevrolet Silverado LTZ Z71 5.3 Aluminum V8 (My daily)
2007 Pontiac G6 VL 2.4 I4 (Wife's Daily)