P0478 code definition In the event that the PCM stores the P0478 code, it means that there has been an abnormally high voltage reading from the exhaust system back pressure control valve circuit.
What is a exhaust pressure control valve?
The exhaust pressure control valve detects changes in the pressure of the exhaust gases to properly control the flow of exhaust gases through the EGR system. They are commonly found on vehicles equipped with turbo diesel engines, however they can also be found on the EGR system of gasoline engines as well.
What is code P0470?
Code P0470 stands for Exhaust Pressure Sensor Malfunction. Some vehicles (mainly those with turbocharged engines) have an exhaust pressure sensor (EP). This sensor does exactly what the name implies – it measures exhaust backpressure.
Where is the exhaust pressure control valve located?
This valve can be found on the body of the turbo, and what it does is monitor the changes of exhaust pressure. It is then able to make the necessary changes to the vacuum. Without this part working properly, your engine will start to suffer as will the amount of exhaust your vehicle is producing.
How do you check exhaust pressure sensor?
If you want to check the sensor while it’s still attached to your vehicle, use a multimeter and vacuum pump to test the pressure and voltage readings. Otherwise, you can remove the sensor and test the electrical resistance between the ports.
What are symptoms of exhaust back pressure?
The symptoms of exhaust back pressure include reduced engine power, poor fuel economy, slipping transmission in the case of automatic cars, altered shift points, among others.
How does a DPF pressure sensor work?
How does a DPF pressure sensor work? The DPF sensor measures the pressure drop across a DPF. A DPF pressure drop increases with increase in the soot mass accumulated in the DPF. Small soot mass accumulation results in lower DPF pressure drop, while high soot mass accumulation would yield higher DPF pressure.