Rev's Dropping Off When Cold

[Obey_R 23]

Well after the car got very hot when the fans didn't kick it, the rev's have now started to drop to the point of stalling when it's cold.

 

When I got the car it would do this to an extent, you had to blip the throttle when it was cold but once warm it's fine. I then replaced a couple of loose/cracked pipes and all was fine. But since the overheating incident, it now drops off again until it stalls when cold, when warm it idles fine. I noticed the pipe going from the SAD to near the AFM (is this to, or from?) was loose, thinking an air lock would cause these problems I plugged up both gaps, in the SAD hose and where that has broken off from, and it didn't change. I then took my thumb off the SAD pipe, no chance, then took it off the hole near the AFM and still no change. I can understand the SAD pipe not making a difference when cold, but surely the hole on the K+N adaptor would make it run like s*it?

[Obey_R 23]

So I just started when it was cold, blocked off the SAD pipe with my thumb and the hole it came from on the TB and it idles very well, let my thumb off the SAD pipe and it dies instantly, so hopefully that means the SAD is working, because when hot it makes no difference.

 

Should mean that my problem is mainly down to the broken SAD pipe/throttle body connection - so just need a new K+N adaptor now!

[Obey_R 23]

Just thinking about this some more, the engine is cold (ish) about 1bar on the temp gauge. It starts okay with the SAD blocked off, so effectivly not working. When I let even the smallest amount of air into the pipe to the SAD struggles to idle. Shouldn't letting a small amount of air through the SAD make it rev higher rather than kill it instantly?