[Wrecked944]

My 964 idles VERY low and even stalls when it is cold. It has 12 new ignition wires (thanks to Chris Bennet) and 2 new caps and a new air filter. So I am guessing (emphasis on "guessing") that the ICV may be bad. So I removed it and cleaned it thoroughly (apparently a "dirty" ICV is a common 964 problem). But while it is out, I wonder if I can actually test it. I mean, I don't even know how the damned thing is supposed to operate. And if it can't be bench tested, then would using a short hose to bypass the ICV (and thus leave the idle curcuit open) help me learn anything? I'm guessing running a bypass hose might make the car run better at idle but run worse (i.e. leaner) at all other rpms. Does this make sense or am I trying to hard?

BTW - A new ICV costs $160+ so I'd really like to diagnose it before simply replacing it.