An air inlet system for an internal combustion engine, the air inlet system comprising: an airflow control component; an air inlet duct (4, 24) which has an upstream end including an opening and a downstream end connected to the air flow control component; and a mass air flow sensor assembly, the mass air flow sensor assembly being located closer to the downstream end than the upstream end, wherein the air flow control component is a turbocharger comprising a compressor and an inlet, wherein the mass air flow sensor assembly includes an air pressure sensor being a Venturi tube, wherein, in the direction of air flow, the compressor inlet comprises an open end engaged with the air inlet duct (4, 24), a convergent region and a reduced diameter region located at the downstream end of the compressor inlet, wherein the open end, the convergent region and the reduced diameter region form the Venturi tube configured to sense a pressure differential upstream and downstream of the convergent region, wherein the reduced diameter region is straight and is located immediately upstream of the compressor, wherein the compressor inlet further comprises two bores (32, 33) extending radially through the wall defining the compressor inlet, wherein first and second measuring tubes (35, 36) within the bores (32, 33) transmit air pressure externally of the compressor inlet to be measured by two measuring ports (74, 76) located in a sensor body of the mass air flow sensor assembly proximate the top of the measuring tubes (35, 36), and wherein the first measuring tube is located in the open end close to the convergent region and the second measuring tube is directly defined by one of the two bores through the wall of the reduced diameter region. an airflow control component; an air inlet duct (4, 24) which has an upstream end including an opening and a downstream end connected to the air flow control component; and a mass air flow sensor assembly, the mass air flow sensor assembly being located closer to the downstream end than the upstream end, wherein the air flow control component is a turbocharger comprising a compressor and an inlet, wherein the mass air flow sensor assembly includes an air pressure sensor being a Venturi tube, wherein, in the direction of air flow, the compressor inlet comprises an open end engaged with the air inlet duct (4, 24), a convergent region and a reduced diameter region located at the downstream end of the compressor inlet, wherein the open end, the convergent region and the reduced diameter region form the Venturi tube configured to sense a pressure differential upstream and downstream of the convergent region, wherein the reduced diameter region is straight and is located immediately upstream of the compressor, wherein the compressor inlet further comprises two bores (32, 33) extending radially through the wall defining the compressor inlet, wherein first and second measuring tubes (35, 36) within the bores (32, 33) transmit air pressure externally of the compressor inlet to be measured by two measuring ports (74, 76) located in a sensor body of the mass air flow sensor assembly proximate the top of the measuring tubes (35, 36), and wherein the first measuring tube is located in the open end close to the convergent region and the second measuring tube is directly defined by one of the two bores through the wall of the reduced diameter region.