Car runs really rough when cold

[PKRWUD]

Kaspar-
I know what you're saying, which is why I suggested the method with which the choke was being operated (signalled) as the cause. If, for example, he has an electric fuel pump, and turns on the key to build up pressure for a few seconds before starting, then the choke will start to open too soon. AND, since the cause would be the driver, the problem would remain with different carbs. Diagnostics are a tricky thing, especially online!

Digger-
You said the choke worked fine. Did the problem occur while you were verifying the choke? The reason I ask is because the only two items I'm aware of that effect idle qualityi n a non computer controlled engine, that change in 15 seconds, are the EGR and the choke. You don't have an EGR valve (correct?), which leaves the choke. If you wittnessed the choke operating properly while the problem was occuring, then we need to start from scratch.

Take care,
-Chris