Explanation:

The name of liquid fueled rocket engine used in both PSLV and GSLV, developed by ISRO is Vikas.

Vikas Engine was successfully qualified through a ground test for a duration of 195 seconds at ISRO Propulsion Complex (IPRC), Mahendragiri, Tamilnadu. Vikas Engine is the workhorse liquid rocket engine powering the second stage of India’s Polar Satellite Launch Vehicle (PSLV), second stage and the four strap on stages of Geosynchronous Launch Vehicle (GSLV) and the twin engine core liquid stage (L110) of GSLV Mk-III.
This engine will improve the payload capability of PSLV, GSLV and GSLV Mk-III launch vehicles.