Surging While Cold

[Alpine TSi]

I have been battling with a pretty nasty case of idle surge with my 92 TSi AWD. I have done almost everything I know of. New coolant temp sensor, ISC, TPS, clean as a whistle TB and pleny o' idle adjustments. As of now I have the BISS bottomed out and with the ISC in the middle( those two pins grounded out) it is around 900 rpm af normal temp. I can't even get it to go to 750. But I didn't have surge unless I started driving it before she was at normal temp.
Now that it is getting damn cold out it surges like mad during warm up and as soon as it gets to normal temp it stops. I don't know what else to do except for a single suggestion of replacing the FIAV. I happen to have one laying around and more than likely will try that soon, but was curious if anyone has had any experience in just blocking that part of TB off and getting rid of those things(I think the ISC is on that part too). Are there any downfalls of that other than a hard cold start? And what does the ECU do if the ISC isn't there? Just some thoughts but I hate telling the idiots at my work that car surges like that so it warms up faster and that it is trubo car thing(they are displacement idiots anyways).

Thanks in advance

[1ViciousGSX]

Try the FIAV and check for vacuum leaks. Also check for un-metered air getting in after the MAF.

[Alpine TSi]

If it were a vac leak or unmetered air, wouldn't it be surging all the time? It only surges while warming up. I think I will try the FIAV tomorrow depending on the weather. Damn cold ass non insulated non heated garage...

[JET]

I would do the boost leak test like Vicious said.

[A//// Guy]

Its the TB... the FIAV is the problem... the wax pellet in there needs to warm up and melt and then it will stop surging. I dont know exactly how it works but the wax melts and covers a hole fore fast idle or something...

Im going to try and replace mine soon. I know thats what it is and Im pretty sure you have the same problem. Its not a boost leak...