On the zzzzz sound.... I can actually hear my high idle circuit... (can't remember its correct name). It make a slight hissing, buzzing noise, which obviously goes away when the engine fully warms up and the idle speed settles down to 575-600rpm. Fully normal, I presume.
I guess there are a million things that might cause hard starting in a 20 years old car. Is all OEM equipment in place and unmodified? All vacuum tubes etc intact? Does it run ok when fully warm?
What color is the smoke? You say oil/water.... I presume it is white/gray, eh?
Personally I would start by hooking up the ECUtuner to see what exactly is going on
. I can not stress enough how important true information is in diagnostics....
Then I would check how fast the fuel pressure builds up when you turn the key first time.
Is the oil contaminated with water? You can have the gas in the radiator analysed for exhaust contamination.... a clear indication of potential head gasket problems...
There's just so many things to check and a lot of info needed.
Kind regards,
Tapani