Powertrain, generic · Auxiliary emission controls

P047B Exhaust Pressure Sensor B Circuit Range/Performance

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

The exhaust pressure sensor measures the pressure ahead of the turbine or in the manifold (Ford: turbine upstream pressure, Cummins: exhaust manifold pressure, older Ford diesels: EBP). The module uses it to calculate EGR flow, to control the variable turbine and engine braking, and to protect against overpressure. No manufacturer document available to us uses sensor B – it would be a second sensor, for example on bank 2 of a twin-turbo engine; the description mirrors sensor A. P047B is the plausibility check of sensor B – with the engine off it should read ambient pressure, in operation it should match the model or sensor A (for sensor A Ford uses 15 kPa).

Likely causes

Sensor drifting or faulty
Sensing tube or hose blocked or coked
Real high back pressure from a clogged particulate filter or catalyst
Leaking sensing tube or exhaust leak ahead of the sensor

Symptoms

  • Check engine light on
  • EGR and turbo control on a substitute value, possibly reduced power
  • Exhaust brake or warm-up flap without function

Repair estimate

DifficultyMediumDIY possible
Parts and labour€60–500
Time0.5–2.5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

exhaust pressure sensor bsensor wiringengine control module

Related codes

P0471P047AP047CP047D

References: law.cornell.edu, fordservicecontent.com.