Ibought a 1979 450sl with mechanical fuel injection. It cranked it over for a long period of time, cold or hot. I replaced fuel accumulator and it starts fine now, but the idle goes from 1000 to 2000 rpms until the motor gets warm. Then it idles at 750 and runs fine. How can I fix this?
Check that the idle air control valve is working, I think that it is located at back of the fuel distribution head in the manifold low down, there will be a large plastic pipe going in and out, one of the pipes may be under the manifold so it may be hard to see and reach, look here.