The O3 and O4 series (“Orbita-3” and “Orbita-4”) were considered the final ones in the Izh-2126 project. In the third series, the final design of the car was found, and the fourth was a pre-production version – with adjustments made based on the results of testing the prototype in a wind tunnel with the participation of Renault specialists, as well as with clarifications on the chassis and components.
In 1984, the Izh-2126 series O4 successfully passed state tests. However, in December, Dmitry Fedorovich Ustinov, the USSR Minister of Defense and the “patron” of the Izhevsk Automobile Plant, died. After this, the amount that was planned to be allocated for the serial development of Orbit began to rapidly decline and the plant had to prepare a simplified version of the Izh-2126-O5.