Hi again!
The solution of my problem proved simple...
In setings of COM port i change "latency timer" to 8 msec, and that's all...
I apologize for my dumb question, the answer was already in this forum.
viewtopic.php?f=5&t=769&p=2084

Hi Yani!
I have a problem with conection with my car- Alfa Romeo 145 1.9JTD, EDC15C5.7
Interface is Vag-Com, with FTDI chip FT232BL.The driver is the latest, from oficial site.
With Vag-Com working fine, but with your program not... I try with different baud rates, but no result...
Any ideas?

Thank You, the problem is solved...
I change the registry, and everything is fine!

No conection with ECU - interface is "K-L" adapter, USB->COM with PL-2303 chip.
With hardware COM port no problems...
Any ideas?