Cold start valve on 1992 Mercedes-Benz 300E

Problems with starting. Replaced distributor cap, rotor button, spark wires, spark plugs and crank shaft sensor but
still having starting problems and car running rough. Suggestions. Thanks

1 answer 1 comment
make sure the o-ring under distributer cap is not worn. check to see if wet inside and any wear on the o-ring.
Thanks. My mechanic in addition to changing the above parts had to change the idle control valve. No more rough riding and car is starting up and running tops.