The cold start valve is at the end of the intake plenum. There is a 7?mm
headed screw on the middle of it. If you remove it and crank the engine when
it is cold, you shoul see gas come out the screw hole.

That valve is BIG $$$!  Wht do you want to remove it?  #100 here:
http://www.detali.ru/cat/oem_mb2.asp?TP=1&F=108019&M=130%2E980&CT=M&cat=230&SID=
14&SGR=001&SGN=01

What do you think is wrong?  Most times, the problem is the thermotime
switch.  It is #268 here:
http://www.detali.ru/cat/oem_mb2.asp?TP=1&F=108019&M=130%2E980&CT=M&cat=230&SID=
20&SGR=001&SGN=01