probably wont make a noticeable difference when fired from cold, easy to test em use a multimeter and make sure the pins pass current when cold, and dont when car is warm. if its bust swap it out but i don't think it would cause the probs you are seeing.
the rev thing is what should happen so the 1.6 is all good

Assuming the 1.8 is still on the 2e2 carb, on the 1.8 check the 3/4 point unit is fully extended when engine is off, and then it retracts a couple seconds after car is started up. look over all the vac lines, and check the choke housing on the side of the carb gets warm pretty much straight after car is fired up, it should get coolant direct from the engine so will get boiling hot pretty soon after engine is fired up.
have a read of the 2e2 carb guide in the mk2 maintenance section, covers just about everything that can go wrong
