The engine will not idle when cold

I would clean the throttle body, idle air control valve, and the Mass Air Flow Sensor (MAF) if equipped. The throttle body gets dirty and wouldn't allow enough air to pass into the engine. The engine will have trouble maintaining an idle until the car reaches normal operating temperature.

This is normal. The ECM monitors engine temperature and increases idle when it sees the engine is cold. The ECM sets the idle back to normal when engine temperature rises.

indicates that the auto choke ( carby ) needs adjusting or if fuel injected , the ambient temp sensor needs replacing

Although your temperature gauge may show that it works, some models have a second temperature sensor for the engine management system.
That second sensor provides info which sets curb idle and timing advance. The "Cold start" feature is a part of this. The hic-cup is something of a bucking symptom as the engine controls toggle between hot and cold run settings repeatedly as water temperature is not stable.
In the past, I found several 1984 engines having defective thermostats which are tied into "Step-up" solenoids for the curb idle. What happens is idle speed is suppose to drop when the engine is hot.
When someone adjusts the curb idle while the engine is on the "cold setting", the setting(rpm) will be too low once the engine has heated up and the part drops to a hot setting.
So to clearly define your problem, you have 2 stemming from the same defects. The "in motion" problem is caused by timing changes based on temperature and the "idle" problem is caused by improper adjustment of the curb idle solenoid because of unstable operating temperature.
What you want to do is change your thermostat. This will give you a stable temperature. Then let the engine heat up and you should notice a "click" and the engine should idle down. It may stall. Then turn the idle rpm up until the engine will not stall.
The hic-cups should disappear once the operating temp is reached. If you still have problems then look for the water temperature sensors before replacing expensive parts.

Hi Malcolm, The cold start operation on all vehicles increases and enriches the fuel to air ratio, making it easier for the engine to start. Most systems also incorporate an 'up idle' which runs the engine at a faster speed until the temperature begins to rise. Regards John

It could be a plugged heater core or heater control problem. I assume the blower is working, but the air is cold. The first thing to check is the coolant level, make sure there is coolant in the resivoir. Next see if the temerature gauge reaches the normal operating temperature range. If the gauge reads cold most of the time, it would tell you that the thermsotat is faulty and not allowing the engine to reach full operating temperature. If your car doesn't have a temp gauge, the blue cold engine light might stay on for an extended period of time. The thermostat is supposed to not allow coolant flow in the radiator until the engine reaches operating temperature. If you drive the car for a couple of minutes, from cold start, the radiator or upper hose should be cool until the engine reaches operating temp.

The cooling fans on this vehicle won't come on unless the a/c is on or until the engine coolant temperature reaches about 220 degrees. Once the coolant has reached this temperature the fans will come and and run until the engine cools down to about 210 degrees and they will then turn off until the temperature climbs up again. The fans usually aren't on at all at highway speeds because enough air is being forced through the radiator to keep everything cool. The true test of cooling fan operation is to allow the car to idle in park with both the a/c and defrost turned off and let it run until the fans come on. When The temp gauge reaches about 3/4 of the way up, give or take a bit, the fans should come on. Keep an eye on the gauge so the engine doesn't overheat just in case there really is a fan control problem but I'd say you'll most likely find that the fans are working properly since they do come on for the a/c. Hope this helps!

Heed of antifreeze solution temperature!!!
You must check the thermostat operating. The thermostat location is on back of alternator at the bottom side of the bracket. IMPORTANT: It is NOT necessary to replace the alternator if you want to change the thermostat !!!
Thermostat checking:
1. Cold engine. Start up the engine and watch of the water temp indicator. After first value 60 Celsius Degree you still warm up the engine until the lifter (pointer) reach 80 C deg. (second mark after 60 C deg.). At this time you let engine running at idle speed and check with your hand the thermostat plastic housing and hose temperature in bottom left side of the engine. Heed of alternator driving belt and ventilator fan !!!
2. If the thermostat is good the hose must be cold until the water temp indicator reach almost 90 C deg.
3. The thermostat opening temperature is 87 C deg.
4. If the hose is already warm the thermostat is out of order.

You will need to check the Mass airflow sensor and the Idle position sensor.

swng,
1) Is the service engine soon light ever on when engine is running?
2) Per your description I would look at the ECT sending unit. It sends coolant temperature information the the Engine Control Module for proper fuel delivery for cold engine start. It may have lost its calibration.
Let me know.
Regards,