Powertrain, generic (extended)

P22CF Turbocharger Turbine Inlet Valve Control Circuit/Open

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P22CF points to an open drive circuit of the turbocharger turbine inlet valve, the exhaust-side valve that either lets gas skip the small first-stage turbine of a series two-stage system or isolates a second turbine in a parallel-sequential layout. GM's diesel OBD tables (17OBDG04 and 18OBDG04) group P22CF, P22D0 and P22D1 as the faults of the high-pressure turbine bypass actuator (HTB); while one is active, boost control leaves closed-loop operation. A GM patent on a series-sequential turbo shows this bypass valve with both a current sensor and a position sensor. With the circuit open the valve sits in its spring position, often causing slow boost or a power cap. No public source gives GM's thresholds for P22CF; the electrical check runs whenever the actuator is in use.

Likely causes

Actuator connector loose, heat-damaged or corroded
Broken wire near the exhaust manifold or turbo
Open winding in the turbine valve actuator or its control solenoid
Faulty output stage in the engine control module

Symptoms

  • Check engine light on
  • Reduced power, boost control in fallback mode
  • Turbo lag or a missing second-stage push

Repair estimate

DifficultyMediumDIY possible
Parts and labour€40–900
Time0.5–3 h

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

Parts involved

turbochargerturbine inlet valve

Related codes

P22D0P22D1P22D2P22D3P22D4P0033

References: gsi.ext.gm.com, patents.google.com, law.cornell.edu.