I am getting near the end of refurbishing a 1987 Turbo with 5 speed. I am having a problem getting the base idle set properly. I have grounded the correct lead to set the idle and thoroughly cleaned the throttle body. When I turn the needle valve on the throttle body clockwise to reduce the revs I can only get them down to 1000 rpm. I checked the timing and it was at 20 degrees. I turned the distributor to reduce the timing but could only get it to 15 degrees BTDC when the distributor was turned all the way to its end of travel. At this setting the timing mark seemed to move about 3-4 degrees continuously when viewed with the light. I had previously marked the crank pulley to see if the rubber had deteriorated but the mark indicates that the two parts of the pulley are stable.

Any help would certainly be appreciated. Thanks

Gary