Fuel and air

P006C — MAP and Turbo/Supercharger Inlet Pressure Sensor Correlation Fault

Severity: medium Drive with care, to a shop

What P006C means

The engine control unit compares the manifold absolute pressure (MAP) sensor signal with the pressure sensor at the turbocharger or supercharger inlet. On a healthy system these readings track each other according to engine load and boost. When the difference exceeds the allowed limit, the ECU sets P006C and can no longer trust its boost calculation.

Symptoms

  • Check Engine light on
  • Reduced power and sluggish acceleration
  • Worse fuel economy
  • Hesitation or rough idle
  • Hissing or sucking noise from the intake
  • Limp mode with limited power
  • Unusual turbocharger noise

Possible causes

  1. Failed MAP sensor
  2. Failed turbo/supercharger inlet pressure sensor
  3. Open, shorted or corroded wiring or connectors
  4. Boost leak or vacuum leak
  5. Faulty turbo actuator or position sensor
  6. Sticking variable geometry mechanism
  7. ECU software or internal fault (rare)

How to diagnose

  1. Read all codes and freeze frame data, looking for other boost or pressure codes
  2. Inspect intake pipes, intercooler, clamps and vacuum hoses for cracks and leaks
  3. Check connectors and wiring at both sensors, including power, ground and signal
  4. With the key on and engine off, compare both sensors in live data; both should read near atmospheric pressure
  5. Compare commanded and actual boost under load
  6. Check the turbo actuator moves smoothly through its full range
  7. Verify a suspect sensor against a known-good reference or a manual gauge
  8. Check for available ECU software updates

Common fixes

  • Replace the faulty MAP sensor
  • Replace the turbo/supercharger inlet pressure sensor
  • Repair damaged wiring or connectors
  • Fix boost and vacuum leaks
  • Repair or replace the turbo actuator or variable geometry mechanism
  • Update or replace the ECU as a last resort

Questions and answers

What does P006C mean?

The ECU found that the MAP sensor and the turbo inlet pressure sensor readings do not agree. The cause can be a sensor, wiring or an air leak.

Can I drive with P006C?

Briefly and carefully, to get it diagnosed. Power loss and limp mode are possible, so do not put off the repair.

What should I check first?

Look for leaks in the intake pipes and hoses and inspect the sensor connectors. Then compare both sensors with the engine off; a large difference points to a bad sensor.

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.