Boost Pressure Sensor

It controls boost. It often includes temperature. Oil can contaminate it. Comparing its reading with the barometric pressure sensor with the engine off is a quick plausibility check. Oil from the crankcase ventilation can coat the sensor and slow its response. Many engines combine boost pressure and intake air temperature in one sensor. Cleaning with a suitable sensor cleaner can sometimes restore a contaminated sensor, but replacement is often needed.

A pressure element sends a voltage signal.

Wrong readings cause power loss. Check hoses for leaks.