White smog and rough idle when cold

[atlyn]

I have a 1990, 911 that I bought a month ago. Among many other things, there are two nasty issues I need help with. When cold, the engine runs rough and will stall without pedal action. Also, white smog comes out of the exhaust like a nuclear power plant. Two, three minutes later, motor idles and smog disappears. I have checked the idler control valve. Took it off cleaned it and hooked it up to a battery. It flips up in a milli second. Is that all it does? My second problem is the DME. To get the car back to square one, I bought a Durametric diagnostic hardware. All the displays are showing up as designed, except the information on the motor. Nada. No vin No. RPM's nothing. Any ideas would be appreciated. Atlyn.

[PNine64]

White smoke is probably normal.
Get a DME relay and see if that works ($20). If not, keep for when it does.
This link has some good info too...High Rev at Idle - Rennlist Discussion Forums

[atlyn]

Thanks PNine 64. Already done some time ago. The Durametric shows a fault with the Oxygen Sensor. Has to wait awhile. Have to assemble the front first. Completly rebuilt the front with new Bilstein, rotors, disks,springs, joints, bearings, brake lines, sensors and powder coated the whole kit and kaboodle. But I will check the "micro switch" tomorrow.