This is an induction tube and the one on the 1.2 item 1a




Undo the jubilee clip holding it on the throttle body and pull it off and push it to one side.. now you should be able to see the flap inside.
This isnt a stilo throttle body but you can clearly see the flap in this one..





Carefully push open the flap and with some carb cleaner.. clean inside and both sides of the flap and where the flap seats with a cotton wool bud or similar to remove any build up of soot and residue.. idle should then return to normal..reconnect the induction tube to the throttle body ..tighten up the clip and fire up the engine..idle should then be restored to around 800 revs..

Just one point to add here and that is on the 1.6 variant and specifically on the phase one cars fiat did introduce a software update for the ecu and throttle body ..this is called a flash and sets new parameters for the running of the 1.6 engine ..so if you have done the throttle body clean up and your problem still persists then contact your local dealer for an investigation and to see whether or not the software updates have been performed on the car..

Good luck and happy stilo motoring..

This is also known under the name of ..butterfly flap..inlet control valve etc ..they are all the same item..contamination can cause the revs to rise and falling quite drastically

Here is the throttle body on the 1.2/4 engines..1c




And on the 1.6 engine..




1.8..



2.4 ..



They all do the same job and to get to them you first of all need to get the engine covers removed..left hand one on this pic..Muppet 42's 1.2..on the 1.2 and 1.4 its an airbox..



Aherm nice colour muppet42..

And here is a cover of the 1.6 ..others are the same ..




Once you have that item off the top of the engine you can then remove the induction tube from the throttle body..

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