QUOTE (stuartm @ Oct 5 2008, 08:16 AM)

clickNot a brilliant pic (you can hardly see it there, obscured by the diaphragm) but you get the idea, its a cylindrical thing, with the connector on the top and the air hoses on the bottom, it sits in a rubber mount sort of thing thats attached to the engine lifting eye. I'd also check the vacuum pipes that goto the map sensor (in the ecu) - if its getting a wrong map reading it can behave pretty weird.
I had a similar issue, turned out to be the throttle position switch. Clean the idle air motor and go for a drive, or swap it out as its a common bosch part. My car would either idle too high or too low, once I replaced the switch, issue resolved.