What Causes Excessive Turbocharger Boost Pressure?
2 Answers
Turbine charger used for a long time, carbon deposits not cleaned in time or poor combustion in turbocharged diesel engines, severe carbon deposits, causing nozzle and turbine passage blockage; failure of the fuel injection pump governor in turbocharged diesel engines, or exhaust valve sealing not tight leading to exhaust leakage; turbocharged diesel engines overspeeding or overloading, increased fuel supply, all can cause the turbocharger speed to rise and boost pressure to increase. Introduction to Turbocharging: A centrifugal compressor and turbine combined into one unit is called a turbocharger. The main difference from a gas turbine is that this unit does not have a combustion chamber and corresponding system; the turbine operates using the exhaust energy from reciprocating internal combustion engines, and its centrifugal compressor provides compressed air as the charge for reciprocating internal combustion engines. Classification of Turbochargers: Turbochargers are divided into radial flow turbochargers and axial flow turbochargers based on the type of turbine.
Excessive turbo boost pressure is a common issue I've encountered, often caused by a stuck wastegate valve - that small component responsible for regulating exhaust flow. If it fails to open or becomes stuck, excess exhaust gases directly impact the turbo, causing pressure to spike. Another frequent problem is piping leaks, particularly loose or aged intake pipe connections that allow air leakage, sending false signals to the ECU which then mistakenly increases boost pressure. Sometimes the turbocharger itself may have damaged blades or worn bearings leading to over-boosting. Additionally, improper ECU settings, such as programming errors or faulty MAP sensors, can cause incorrect readings. High boost pressure risks engine damage including piston and head gasket failure, even detonation, with symptoms like sluggish acceleration and abnormal exhaust notes during driving. Regular inspection of the wastegate valve and piping seals is crucial, and professional diagnostic checks are highly recommended.
