flap advice

[hankino]

Hello all,
Can you help?

I've got a problem with my (ahem) E30 316 M10 carbed baur - I can't work out how to test whether the warm air intake system is kaput.

I know it's not an E21 but knowledge about the carbed E30s seems almost non-existent these days, and it's an air filter intake design like the one on the carbed E21 316 - some sort of vacuum and spring arrangement controls the flap.

My flap's covering the cold air intake at start-up (fair enough), but applying vacuum only seems to close the flap tighter - so basically I seem to be running with hot air all the time, which can't be how nature intended can it?

Anyone know how these things are supposed to work, and how to test if it's knackered?

any help appreciated
Alex

BTW it's a weber dmtl conversion

[nas80]

where abouts are u, I have a spare airbox u can try?

[hankino]

that's kind of you nas, but I'm down in Kent.
do you know how this thing should work?