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Turbocharger Inlet Pressure Sensor

Measures pressure before the turbocharger's compressor — the stretch of intake everyone forgets, which runs below atmospheric because the turbo is sucking through the air filter and ducting. That depression is a measurement with two jobs: it monitors air filter restriction honestly (a clogging filter deepens the depression at any flow, so the service warning comes from physics rather than mileage), and it guards the compressor's operating range, which depends on inlet conditions. Twin-turbo engines carry one per inlet, which is where the B designator comes from. The free check its codes allow: engine off, the reading should equal atmospheric exactly — disagreement at rest convicts the sensor, while a deep reading only when running may be the sensor doing its job on a blocked filter.

Also known as: compressor inlet pressure sensor, turbo inlet pressure sensor, inlet depression sensor, pre-turbo pressure sensor, supercharger inlet pressure sensor

Referenced by 40 codes

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Codes involving this component (40)

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