Classic Audi - Warm up Value pressures

Hi all,

I need to know the correct pressure(s) that a warm up valve should go through from start up to when the engine is warm and running smooth for a 200Turbo (MC).

Recently had the warm up valve replaced and the car is running sh1t since.

The reason the warm up valve was replaced in the first place was an issue with the car turning over too long on start up before starting. The car is tough to start and rough on idle at start up.
There is no fuel holding pressure so I think the fuel pump check valve or accumulator is the problem (already had the fuel pump checked and its ok) but my mechanic who knows (so you would think) this stuff better than I do was sure replacing the warm up valve was the right way to go.

Replacing the warm up valve has not repaired the problem and my mechanic is on a 2 month holiday in East Asia and I am out of pocket and my beloved 200 is running sh1t.

So first to undo the the mess he has made. And to do so I need to know the correct pressures for the warm up valve which I think he has not set correclty.

Open to suggestions from people on how to fix problems with car not turning over after 20+ mins without running. The car is alway tough to start and rough on idle even when the engine is up to temp, HELP!!!!!

As always, input much appreciated!