Turbocharger/Supercharger Boost Sensor B Circuit Range/Performance
Common Symptoms
- Check engine light illuminated
- Reduced engine power or lack of boost under acceleration
- Poor fuel economy
- Black smoke from exhaust under load
- Rough idle or hesitation during acceleration
- Intermittent turbo operation
Most Likely Root Causes
- Faulty turbocharger boost pressure sensor B
- Corroded or damaged wiring harness to boost sensor
- Vacuum or boost leak in intake system
- Clogged or restricted intercooler
- Failed turbocharger wastegate or variable geometry mechanism
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Component Location
Boost sensor B is typically located on the intake manifold, intercooler outlet pipe, or turbocharger housing on the high-pressure side of the intake system.
Manufacturer Notes
Some dual-boost-sensor systems use sensor B as a redundancy check or for specific turbo configurations such as twin-turbo or variable geometry turbos.
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