POTENTIAL CAUSE
1. Air filter plugged.
2. Restriction in air intake duct to turbocharger compressor wheel.
3. Air leak in turbocharger compressor inlet and outlet ducts. May be accompanied by high pitch whine indicating system air leak.
4. Loss of vacuum to wastegate actuator, or actuator is damaged.
5. Air leak at intake manifold.
6. Exhaust leak between cylinder head ports and turbine inlet of turbocharger.
7. Turbocharger damaged internally.
8. Fuel system problem (over-rich mixture).
CORRECTION
1. Replace filter.
2. Remove and inspect duct components. Remove/repair any restrictions.
3. Disassemble, inspect, repair worn, damaged, loose parts.
4. Check vacuum supply. Replace hose and fittings if necessary. If OK, use hand operated vacuum tester to check actuator operation. Replace actuator or vacuum pump, as required.
5. Tighten loose bolts. Or, remove manifold and replace gaskets if necessary.
6. Check exhaust manifolds pipes, and turbocharger connections for leaks. Replace damaged components, tighten loose fasteners.
7. Remove and inspect turbocharger. Replace if compressor/turbine wheels, or other internal components are damaged.
8. Refer to low power information in standard diagnosis.
