IDLE FAULT

[R]

Hi every one i have a gti 16 valve model but have a fault with its idle.First i took it to a garage who put it on their diagnostic machine and said the crank sensor had gone with the way it revs on their machine.They changed it but it did not fix it and they said that they had put it back on to the diagnostics again and it came up with a code which means it needs the ecu resetting.Was told they carnt do it take it to vw so i did,said what was wronge and said what the other garage had done.Vw said they had set the idle and co it was better but the reason behind it is that your throttle body is not very good its at fault.It was ok for a few days but it started to rev again but for them to fit a new body it would cost alot 500 pound just for the throttle body for a start.So i changed the throttle body with a second hand one which i got and was told it worked ok on their car but it didnt work that good on mine.So i changed the potentimeter on the throttle body as i thought its got to be the a sensor on the body went back to vw to order a sensor and they said it is the only one you can change but did not change its idle problem i have with it.I have changed the ecu relay and fuel pump relay suggested by gsf as they carnt under stand it as the cars only done 82000 miles its not changed any think again.Checked all vac hoses replaced the ecu to inlet manifold,throttle body and the small one near the isv still no change so i put the throttle body one back on tried  a new isv on it still the same,ecu temp sensor no difference,full service which a new fuel filter was put on.Now im lost with it carnt seem to fix this fault have you any ideas please and if two garages carnt its bad and its not good with it drinking petrol with it reving like it does,but then it only seems to do it when you have been on and off the throttle driving round a town and its warm which is why i changed the temp sensor thinking that was the fault with it.

[DazVR6]

And breath.............Whats exactly wrong with the idle? it may be me being a bit thick but i couldn't get the gist of it from your first post.

[R]

The fault with it is that the revs seem to stick but only when it is warm example travelling in a place having to be on and of the throttle when stoping at traffic lights or slow moving traffic.The flap on the throttle body seems to be shut well its up to its stop point would not move any futher and the throttle cable dont appear to be sticking as i have tried to give it a slight pull when it is playing up and that makes no difference.Srayed grease, wd40, oil on every think you can take off on the throttle body.But i do get the idea that it is the throttle body as it only does it when you have used it,but then you can also leave it to idle after it has been used and you can hear the revs pick up for a few minutes and drop slightly down with out touching it so i dont no were to turn next.The car pulls ok and i have checked and replaced the vac hoses unless there are some i carnt see but it sounds like its sucking air some where but then you would have thought that garages i have took it to would check all that out.

[Overseer]

if its sticks.. its likely to be a vacuum leak..

[R]

if its sticks.. its likely to be a vacuum leak..

Hi any ideas were to look as i thought i had covered most of it