Carb piston

[joe fremeau]

Hi , My front carburetor is not working when I give it gas the piston does not move, but when the car is off it moves freely. The rear carburetor does not have this issue and works fine does anyone have a idea what it could be thanks.

[keith0alan]

Is the air flow balanced?

[todd lorber]

Are all passages clear (in both the housing and the piston)? They need to be clear in order for the vacuum to lift the piston. Otherwise, there will only be vacuum pulling it down. This could explain why it moves when there is no vacuum at all; i.e. when the engine is off.

[joe fremeau]

Thanks good idea will check