Turbocharger
Definition
A turbocharger uses exhaust gas energy to spin a turbine wheel connected by a shaft to a compressor wheel that forces more air into the engine, raising power and efficiency. Boost is limited by a wastegate (fixed geometry) or by adjusting vane angle (variable geometry, common on diesels), controlled by a vacuum or electric actuator. The shaft rides on oil-fed bearings, so oil starvation, dirty oil and hot shutdowns cause bearing wear, shaft play, oil leaking into the intake and blue smoke; variable vanes also stick with carbon. Symptoms include whistling or siren noise, lack of power, excessive smoke, oil in the intercooler pipes and limp mode under load. Codes: P0299 (underboost), P0234 (overboost), P0045-P0049 (boost control actuator), P2563 (VGT position sensor), P003A (VGT learning).
Codes often stored
- P0045Turbo/Super Charger Boost Control Solenoid Circuit/Open
- P0046Turbo/Super Charger Boost Control Solenoid Circuit Range/Performance
- P0234Turbocharger/Supercharger 'A' Overboost Condition
- P0235Turbocharger/Supercharger Boost Sensor "A" Circuit
- P0299Turbocharger/Supercharger 'A' Underboost Condition
- P2563Turbocharger Boost Control Position Sensor Circuit Range/Performance