Bad news mate.
Another victim of swirl flap failure!
I deflapped mine the other day, replaced the breather and cleaned the EGR valve too, took about 3 hours.
PWM are quite expensive for the blanks, they are available on ebay for £6/ea posted (including new seals).
http://cgi.ebay.co.uk/BMW-Swirl-Flap...item3a59315094