how do you use it to clean the engine? take off the pipes leading to the throttle body and just spray it inside the throttle body when you open the throttle? do this while the engine is running or not? this is for a 350 tpi 1991

 

Carb cleaner wont really clean the engine. if you want to clean the internals of the engine use either SeaFoam or (if carbbed) water. Follow directions on SeaFoam on with water slowly drip it into the engine. The water will clean out carbon. I think seafoam will clean out someother things as well.

 

Spray the throttle body while it is running and 'blip' the butterflies a few times. I do this and then spray enough in to stall the motor then let it set for about 5-10 minutes, when you start it up the smoke will show you it is burning up the gums and varnish. They sell a product called "Throttle-Body cleaner" but any carb cleaner will work fine.

 

Just be careful with the carb cleaner - DON'T look down in the hole while spraying - it's very combustible, and I'd hate to see a backfire blind you! Likewise, make sure there are no unplugged wires - and electrical source can start that stuff ablaze instantly (ask me how I know ).