Hello, I have a 1991. 230 ce with an idle problem. The car does not want to idle, but if it does it’s all over the place, but when I pulled the plug off the back of the rotary idle it would idle, a bit low but would keep going, as long as the car was warm. I tested the rotary idle and the spear one I have and they both seem to be fine. So I was told to test the voltage protection relay, which I finally got round to today. I have 12v on all 30 pins and all 87 pins, they are the ones I was told to test, but I put a tester on all the pins and I also have 12v on pin 15, but pin 31 has a large brown wire going to it and that has nothing. Can anyone help?