How to get to the cold start vavle? on 1993 Mercedes-Benz 190E

I own a 1993 Mercedes Benz 190E 2.6. Its a wonderful smooth riding car but it has difficulty starting in the cold. I assume its the cold start vavle but i have never seen one or know how to replace it. It would be nice if i can get some advice on this subject.

Asked by for the 1993 Mercedes-Benz 190E
The engine uses mechanical fuel injection similar to a lot of VW, Audi,Volvo and Peugeots. The system is sensitive to water contamination, but see if there is any independent European car specialist that has experience in older European cars. It could be the cold start enrichment. but you need a special fuel pressure gauge set up to measure system pressure.
Look up "Bosch K Jetronic" you will find over view of how the system.