Idle problem

i have a 2000 318i e46 with idle problem.
when cold it just won't start or start only about 1 second then die.
if i push accel pedal a little, it start and the rpm steady at 1000 then slowly dropped to 750 as the engine getting warm, then idle becomes erratic but the engine still running, the exhaust smell raw gas. With air-con on the rpm increase to about 900 but still erratic. No-problem at all when i speed the car, but when the car stop the idle is even worse unless i shift to neutral, it returns to it's initial erratic state.
I have checked the ICV and it is OK. Can anyone help me with my problem? Thanks 1998 e46 318i poor starting and wont idle or take any throtel. Ive replaced the breather valve on the injetion manifold and some breather hoses at the front of the cylender head as it would run fine with the oil cap off. Now it wont run atol.