What is the dipole moment of the most stable conformer of 1,1,2,2-tetrafluoroethane?
The dipole moment is 2.45 Debye. The molecule is dipolar as you have asymmetrical electron distribution around both the carbon atoms. 

Source: Complete Structure of Gauche 1,1,2,2-Tetrafluoroethane Determined by Microwave
Spectroscopy, J. Phys. Chem. A, 2000, 104, 9489-9493.