problem with my 1986 16v
 

I have a 1986 mercedes 2.3 16v, that I have owned since 1992. I stopped driving it in 2003, and it became just a saturday drive car until 2 years ago when I garaged it. The problem I am having is that this car has difficulty staying on when initially started and idles between 3000rpm to 0 until it warms up (approx. 5 minutes). Last year I took it to a dealership, and after spending 1,500 the problem was still unresolved.It has recently also failed emissions. May I get some advise from anyone with experience with this unique vehicle.