Idle problem solved
My problem was the following:
The engine starts fine when cold, setting down from 1200 rpm to its normal 600 rpm within a minute. When warmed up, the idle rpm drops so low and it stalls and cannot be restarted until the engine is cold again.
When the engine is started, it would run as long the accelerator is depressed, but once it is released, the engine would die off again.
How it was solved:
I read a lot of threads before beginning to do anything.
Finally I decided to start with the check of the Ignition system. Also I checked first the distributor cap and the distributor rotor.
The distributor cap was burned from inside and the piece of coal was quite completely used; also the piece making the contact with the coal was corroded.
I decided to change the distributor cap and the distributor rotor.
What the result:
I thought the engine starts fine when cold, I was wrong. I was so used to wait 3 to 5 seconds before the engine starts. Now it starts in less than 1 second!!!!
Now the engine idles like silk (cold engine or hot engine).
What I'll do next:
Because of the long time without using this car (not possible to drive) the battery is now out. Then I will buy a new battery.
Next I'll change the injectors.
Then I have to change the silent blocs and the chain tensioner (just for comfort).
Anyway this is a great forum.
Hope this writing will help.