1982 Bus (Vanagon), 2.0 l air-cooled, 4 speed, 125k miles:

Cold:
When starting from cold, ie after several hours rest the engine bursts into
life immediately at the very first turn of the key, with no throttle.

Hot:
Also when starting from hot, ie a few seconds or a couple of minutes after
stopping, start up is instantaneous, again with no throttle.

Warm:
In great contrast to this, when the engine is warm, ie after stopping for
about half an hour to an hour starting takes several seconds or else
several attempts, and only when the throttle is pushed to the floor.

What can be the problem? It has a carburetor, not fuel injection.

Lionel Tun
lionel@dircon.co.uk