It looks like an EVP sensor connector, EGR Valve Position Sensor. I don't see an egr valve in this picture, has it been eliminated or was it ever equiped with EGR?
__________________ Jim
2007 GT California Special, Vista Blue, FRP 200hp supercharger, Ford Racing GTA mufflers, GT-500 rear spoiler, 18" Polished Wheels, FRP lowering and handling kit, FRP short throw shifter. Since the blower install this thing is a rocket. CHE Adjustable Lower Contols Arms and Anti Squat Brackets. I have now changed to GT-500 wheels and tires to allow for the install of the Ford Racing 14" Brembo brake set-up. | 
Please Help New to mustangs and i have no clue 
