Our spy photographers have caught the 2014 Mercedes-Benz E-Class sedan while undergoing some testing.

Once again our spy photographers have caught a facelifted 2014 Mercedes-Benz E-Class sedan prototype while undergoing some testing.

The facelifted E-Class will get the new one-piece headlights and should feature a restyled front bumper and grille, along with some minor revisions to the taillights and rear bumper.

In terms of power, the engine lineup will probably get a bump in horsepower, including the high-performance E63 AMG variant which will reportedly generate 543 hp (405 kW) without the optional Performance Package. Mercedes-Benz might be planning a new entry-level variant with a 4-cylinder, 1.6-liter Renault-sourced engine producing 156 hp (116 kW).

We will have full details next month when the 2014 Mercedes-Benz E-Class will debut at NAIAS in Detroit.

Gallery: 2014 Mercedes-Benz E-Class sedan facelift spied