AU1 extreme rough idle??

[sixty9]

hey guys!

I have an extremely rough idle in drive, rough in neutral and in park.
this problem started off with a very minor rough idle , and has worsened over the months. however when you drive along, it is all good, its only when you are idling where its rough.

i have changed sparks, leads, oil, battery so far. the car has travelled 220k's.

when i disconnect the iac connector at idle, the engine turns off? should it do this?

things i havnt done is O2sensor, coilpack, iac??? or could it be my valves?

like to get some idea's or if anyone else has experienced this?

car is also dualfueled gas/petrol and is the same for both!

thanks for hearing me out!