Hi
Can anyone explain the correct function of the " butterfly valve" inside the air intake housing on the CFI EA/EB motors? and its association with the heating tube from the exhaust. Mine seems to be open all the time and not sure when its supposed to be shut.
Thanks

If it's what I think you mean. The idea of the flap is that when the engine is cold it shuts in such a way that air is drawn thru from the cover on exhaust manifold, putting the warm air into the engine. The idea behind it is more than likely to help stop exhaust pollutants when the engine is cold, or to make the engine run better when cold. Not sure. When then engine warms up the flap moves drawing cold air from the snorkel from the front of the car. They rarely work anyway, and as long as the intake of air is from the snorkel above the radiator it's ok.

thanks mate