car: 1991 560 SEL
problem: hard start, especially in the moring.

My car used to have a high idle problem. It is more than likely a bad throttle position switch. In any case, I could not afford to do the replacement so I stuck a metal with a 5 mm hole into ICV to permanently restrict idle air flow.

On another front, this car has alway been hard to start. The first turn of teh key always get the engine started by it will die right away. I have to crank 3 to 5 more time then the engine will come on. The first 10 - 30 seconds, it will only idle at 400 RPM and the everything could be fine after that.

Based on what I read here, I went ahead replaced the fuel accumulator, fuel filter, and two pump check valves. The car started and ran much better for three days. Now, it still runs with much more power than before fuel accumulator. But the hard start is coming back.

Some where I read that EHA valve should get a 75 ma current at KOEO to provide a rich enviroment for starting. If my throttle position switch is bad, thus the controller may not give that signal for additional fuel because it does not not know I am at idle.

I know how to check current to EHA. But like to know from the experts if my logic is correct. I know muy vacuum, temp senors, etc are O.K.

Thanks in advance