What is a turbo pressure sensor and how can it be repaired? What are the symptoms for a turbo pressure sensor malfunction? What causes a turbo pressure sensor failure?
What is Turbo Pressure Sensor?
The turbo pressure sensor is very similar to the manifold absolutepressure (MAP) sensor. Only the application is different between them. The sensors used in naturally aspirated engines are the MAP and MAF (mass-air flow) sensors. These sensors allow the PCM / ECM/ ECU to monitor barometric pressure and airflow volume, allowing the engine’s optimal air-fuel mix to be set under different loads.
Turbocharged engines however are very different.
This is where the engine uses a compressor or turbine to pump more air into its intake manifold. Supercharged and turbocharged engines often use a combination sensor to measure air pressure. These sensors include the MAP (barometric pressure), MAF (MAP) and BARO(barometric pressure). However, some engines include a turbo pressure sensor as an alternative to the MAP sensor. Other engines may have both.
The air density of turbocharged and supercharged engines is higher. A sensor must be able to adapt to pressures of positive and negative to determine the optimal air-fuel mixture. This is where turbo pressure sensors come in.
The boost pressure sensor measures air pressure from the turbo to intake manifold, and reports it back to the PCM. This sensor data is used by the PCM to calculate the intake manifold’s air density and flow rate. The PCM adjusts boost pressure and injector timing to ensure that the engine operates at its best under all driving conditions.
What are the symptoms of a Turbo Pressure Sensor Failure?
Different vehicle models and engine types can have different symptoms. The primary sign is usually when the PCM’s memory contains one of the P0235,P0236,P0237 or P0238 fault codes and the check engine lamp comes on. The PCM will compare the data sent by the turbo pressure sensor and the MAP (or barometric) sensor. If the PCM notices that the measured pressure falls outside the desired range (too high/low), it will report a trouble code to the PCM.
The turbo pressure sensor may also malfunction if there is poor acceleration or low engine power. This is due to the PCM disabling turbo protection. Other symptoms include slow acceleration, idle speed fluctuations and difficulty starting the engine.
- Illumination of the check engine light
- – Lower engine performance
- – Engine hesitation during acceleration
- Fluctuations in idle speeds
- – Smoke coming from the exhaust
- – Engine overheating
- – Spark plugs contaminated
- – A PCM can enter fail-safe mode, which disables turbo
Why is the Turbo Pressure Sensor failing?
These are usually caused by contamination or normal wear and tear. The check engine light may be on because the turbo pressure sensor may not be responding in time and will need to replaced. The sensor may be still functioning at this stage, but it will soon stop working completely. The only way to fix it is to replace.
The turbo pressure sensor is located in the intake tube near the throttle valve. Because it is constantly exposed, the sensor is susceptible to contamination. If the sensor becomes dirty, it will not be able to measure the intake volume. If this happens, the check engine lamp may turn on. The sensor can be removed if it is still functioning or the values remain within the range. If this happens, the problem could be fixed.
