Hy, I have a VW Golf mk3 1996, 1598cmc.

Hello Catalinmarginean,

I worked at VW South Africa for 11 years, and although models will be different there are some common technical systems. Looking at the symptoms, and the fault codes, it would seem most likely that there is a problem with your idle stabilisation system. If your car is fuel injected, then there are usually two complementary systems - digital idle stab by moving ignition timing (quick, but limited effect) and a servo-motor on the throttle for bigger demands (like aircon or power steering).
The second FC ("leerlaufregler - inactiv controler") indicates that the second idle stab system isn't working, which is why you have problems when the engine is cold. The parasitic losses are higher, and the alternator is loading the engine recharging the battery after the start, and the digital system can't cope.
The first FC would tend to indicate the base timing setting hasn't been done. The whole timing map can be moved (on some VWs at least, not sure on yours) by moving the distributor) To set the base timing, the digital idle stab has to be switched off temporarily, done by a VAG machine (like 1552 or 1551) at a dealer. If this has not been done, the timing may be out (more likely retarded) and this will also affect the engine.
I would get the base setting done, and check the throttle servo - usually movement can be seen on the throttle butterfly shaft. If this is not apparent at idle then either the servo or the wiring is faulty.
The last FC iten is the option to clear the fault memory. This should be done, and then it should be rechecked after running to see if anything recurs.
Hope this helps.
Africangrey