Blow-through sensors are located after the supercharger, turbocharger, or intercooler, just before the throttle body.

Blow-through sensors are located after the supercharger, turbocharger, or intercooler, just before the throttle body.

• A. Blow-through
• B. Draw-through
• C. Hot wire
• D. Film sensor

Answer: (A)

Blow-through refers to a sensor placed in the boosted air path, after the compressor and before the throttle body. This placement ensures the sensor measures the actual mass of air entering the engine under boost, which the ECU uses to meter fuel correctly. Draw-through would place the sensor in a different location and could read air conditions that don’t reflect boosted conditions as accurately. Hot wire and hot-film describe how the sensor senses air, not where it’s located, so they don’t define the placement. Therefore, the described arrangement is characteristic of blow-through.

Blow-through refers to a sensor placed in the boosted air path, after the compressor and before the throttle body. This placement ensures the sensor measures the actual mass of air entering the engine under boost, which the ECU uses to meter fuel correctly. Draw-through would place the sensor in a different location and could read air conditions that don’t reflect boosted conditions as accurately. Hot wire and hot-film describe how the sensor senses air, not where it’s located, so they don’t define the placement. Therefore, the described arrangement is characteristic of blow-through.