I hope you can help. My G40 has this really annoying habit of running rough as if on 3 cylinders on cold morning start up. It's not for long though probably not longer than 30 seconds if you move away straight away but it seems to have other small problems that I think are related. It idles fine but seems to have an occasional hiccup when warmed up too as if the throttle is quite sensitive when you release the throttle when driving . It's done the cold morning thing for ages now and since then its had, new, and vag too, lambda probe, blue temperature sensor, W5DPO's, new coil, dizzy cap, rotor arm and ignition leads. All earth leads are fine too. I've checked the voltage across the battery and it was at a mininum 13.7 with EVERYTHING on which is fine. I've checked the ohms on the Co pot which is set at 550 ohms, again fine.
The strange thing is the car drives pretty well, boosting really well, it's more so at slow speeds that it seems slightly sensitive. This morning I got a whiff of petrol but that went away quickly but it always does it really i suppose. There are no petrol leaks, all vacuum pipes are attached and secure and all plugs have been checked and wd40'ed, both fuel pumps are new vag too.
Occasionally, and its ALWAYS when the lights are on the car will stall when started cold. Usually when I get to the bottom of the street. It's not always though just occasionally?? It always starts straight back up and idles fine all the time.
It's proper random and i have no idea what to do now. the car is lightly modified:
Dewedge
Decat
Full blend
Derestricted
I wouldn't say my fuel consumption is amazing either but its not horrendous.
Is it possible my timing is slightly out? this is not something i know how to do and dont even have the equipment.... Some suggestions please...
HELP cos it's getting on my TITS!