In the correlated narrow-gap semiconductor FeGa3, 1.25Ga atoms per formula unit can be replaced by Al atoms providing chemical pressure of1.2GPa. The resulting FeGa3-yAly solid solution (0y1.25) crystallizes in the parent structure type with Al atoms preferentially occupying one of the two crystallographic positions of Ga. As revealed by electrical resistivity and heat capacity measurements, FeGa3-yAly exhibits nonmetallic properties for y=0.937(9) similar to the parent compound FeGa3 demonstrating that the electronic structure is not significantly altered by the chemical pressure. This result is corroborated by the electronic structure calculations, which show that the band gap is only slightly reduced in FeGa3-yAly for y=1.