What does the dashpot on a car do?

Question

My car loses power when I first start the engine but once it warms up it works good.

Answer 1

A dashpot is a small diaphram that has a rod that pushes against the throttle linkage to slow the closing of the throttle butterfly or flap so that a groove does not get worn into the throttle body from the throttle snapping shut too fast. On older cars it also helped a bit with emission control. You have other issues with the motor causing the lack of power. I'd take it to a mechanic rather than guess on the internet.

Answer 2

If you are thinking of the choke knob for a carburetor --

Carburetors need to come up to temperature a little before they operate efficiently and responsively. The choke restricts air and/or richens (sometimes called an enrichener) the mixture (more fuel, less air) to help get your engine started and warmed. The colder your environment the harder it is to start most carbureted engines.

The engine itself, more than the carbs, works better at operating temperature. The oil gets to the right viscosity. The spark plugs achieve the correct heat. And mechanical tolerances (e.g. pistons) all expand to the correct (designed) values.

This is a big advantge of good fuel injection over typical carbs, less warm-up time required to run well.