troubleshooting a surging idle/low idle

[mlozzi200478]

hi,my idle has been strong when cold,when warms up the idle surges up and down,from 800-500,then when turning wheel it adds to much load,and engines stalls at times.it has a brand new idle control valve.i just replaced the vacum line to the fuel pressure regulator,it was snapped in 2 pieces.the valve cover breather was cracked,replaced that.is there a mass airflow sensor on these 89 300ce mercedes,ora throttle position sensor?how about if the throttle bore is very gummed up/dirty will this cause a surging idle,do i need to dump a can of top engine cleaner down the throttle bore?the electro hydraulic actuator is currently defective,i got a new one but it needs to be calibrated,but thats only to assist in cold strats.im lost???

[mbdoc]

Does the engine surge at idle with the idle valve disconnected?

[mlozzi200478]

yes it does,it surges both ways