Engine

P00FB — Turbocharger Outlet Pressure Sensor A Circuit High

Severity: medium Drive with care, to a shop

What P00FB means

The engine control module constantly monitors the voltage signal from the turbocharger outlet (boost) pressure sensor. P00FB is stored when that signal rises above the allowed range, higher than real boost could produce. The usual culprits are the sensor itself or its circuit: a signal wire shorted to power, an open ground or a poor connection.

Symptoms

  • Check Engine light on
  • Reduced power and sluggish acceleration
  • Limp mode
  • Abnormal or unrealistic boost readings
  • Hesitation or rough running
  • Possible unusual turbo noise

Possible causes

  1. Failed turbo outlet pressure sensor
  2. Damaged wiring harness or signal wire shorted to power
  3. Open sensor ground
  4. Corroded or loose sensor connector
  5. Rarely, an ECM fault or incorrect signal interpretation
  6. Related boost system faults: actuator, sticking variable geometry mechanism, air or vacuum leaks

How to diagnose

  1. Scan for codes and freeze frame data, and look for other boost-related codes
  2. Inspect the sensor connector and harness for chafing, melting, corrosion or moisture
  3. Read boost pressure in live data with the engine off and compare it to ambient pressure
  4. Test the 5 V reference, ground and signal at the sensor connector with a multimeter
  5. Check the signal wire for a short to power and for continuity to the ECM
  6. Compare specified and actual boost on a road test
  7. Check hoses, vacuum lines and turbo actuator movement over its full range
  8. Swap in a known-good sensor if needed, clear the code and see whether it returns

Common fixes

  • Replace the turbocharger outlet pressure sensor
  • Repair or replace the damaged wiring and connector
  • Clean the terminals and remove corrosion
  • Fix air or vacuum leaks or a faulty turbo actuator
  • If an ECM fault is confirmed, repair or replace it and program it

Questions and answers

What does P00FB mean?

The ECM sees an abnormally high signal from turbocharger outlet pressure sensor A. It usually points to a bad sensor or a wiring or connector problem.

Can I drive with P00FB?

Only carefully and for a short distance, such as to a shop. Power is likely reduced and boost control may not work correctly.

Will replacing the sensor fix it?

Not always. Check the reference voltage, ground, signal wire and connector first, or a new sensor may not cure the problem.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.