I have a 1992 MB 190#, 2.3L. Recently we have been having a hard time starting it when the engine is cold. I have checked everything that most of the shops have told me to check, however, based on some earlier Volkswagen experience, my mind is made up that it is my cold start valve. All fuses are OK, with no corrosion, and the 10 amp blade fuse in the over-voltage protection relay is OK. I have disconnected the electrical plug to the valve and checked the connections. They are OK. I'm about ready to gamble and buy a cold start valve. ANy other simple checks that I should try. Any help would be appreciated.