Hunting idle on a 16v
What is the most common cause of a hunting idle in a 16v. It happens in my car mostly when it is cold. The idle will fluctuate from 600 to 1100 at idle. It will never stall, and after it warms up it generally levels off at about 950. I replaced the coolant temp sensor (the big green one at the front of the thermostat housing) which regulates the idle before the oxygen sensor warms up, but are there any other sensors that are suspect? Thanks in advance.
1985 190E 2.3-16 Euro