My 1986 560 SEL has just recently started idling at 1700 rpm and it starts very hard in the morning. I've been told that it might be the overload protection relay fuse, but the fuse looks fine and when I pulled the entire relay out while the car was running, nothing changed. I was also told by a mercedes tech that it could be an idle control valve; again, I pulled the power from the valve while the car was running and nothing changed. Could this mean that both the valve and the relay are bad?
Any suggestions would be greatly appreciated, thank you.