GSI - coasting air valve/idle limiter valve problem?????

[vastre]

I baught a new coasting air valve for my Gsi, the revs used to stick up at about 2000 RPM and there was no adjustment left in the old one (screwed right in). I have fitted the new one and it still does the same thing, i pinch the pipe at the top of the valve and the revs go back to normal.
Does anybody know how these things work and should it be set correctly from the factory as it is brand new?
Does the vacuum at the bottom open or close the valve, i can't work out quite how it is suppose to work. The revs will stick @ 2000 then all of a sudden die down to normal, then as i touch the throttle it goes back up to 2000..............
Does anybody know?

TIA

[Dicko]

check the pipes are ok, and geting a good seal, if u have a new 1 and it sems to b this cuasing the problems im unsure!! the next thing to do is make sure all pipes r connected properly, in the right place

[vastre]

i have just noticed that if i am driving along and i knock the car out of gear, the revs are sticking about 2000 then if i press the brakes pedal they drop back to normal.....................hmmmmmmmmmm..weird

[Dicko]

do you have the later hgsi with multec injection?

if so u will have a thin tube conecting to the valve on the pipe that joins ur brake sevo to ur engine!!

sounds like it aint connected up properly

[GARY]

Mine did exactly the same thing and i found it to be the Throttle valve switch on the back of the inlet manifold also check the wiring plug that connects into the switch. I would recommend getting second hand as new ones are ?65 :( hope this helps :D

[vastre]

the injection is Bosch later type ( ecu on air flow meter) with siemens box for spark control.

I have had to virtually screw the thread on my new valve right in to get the idle to stay steady 900 approx. Obviously the vacuum in the manifold opens the valve to let air in when your coasting on closed throttle. At idle surely this valve is not suppose to open at all, but clearly mine is opening for some reason, how can i have too much vaccum at idle??? it doesnt make any sense at all. If i discoonet the vacuum pipe form the bottom (and plug the end) of course the valve doesnt open and it idles fine.