Low idle

[WidowmakerS2]

Hi,
My 3b is giving me massive headaches. The trouble is idling, and the occational stalling when coming down from higher rpms. My typical idle is around 500rpm cold/warm.
I looked around too see if I could find any air/vacuum leaks, and tightened some loose clamps in the breather system. This seemed to help with the stalling, but did nothing with the idle.

Stange thing is that this happened before too, when the car had a 7A in it. Leads me to think either fuel pump/reg or some part of vacuum system that wasnt switched.
No fault codes.

Ideas?

[A80Avant]

try undoing the MAF and give it a nice clean. Then undo the ISV valve(little barrel behind the inlet manifold) and clean that as well with a brake cleaner spray.

[simon20vq]

I reckon you have a partially blocked breather pipe. Does the oil cap show any signs of a milky film? If it was the ISV it would be fine when warm or vice versa. The block is starving the engine of air. Has it been standing a while before you used it? Try and get the engine nice and hot by driving it and if you've not changed the oil recently do that after its cooled down.