What is VSV for EGR?
This constant vacuum supply flows to the EGR Vacuum Switching Valve (VSV), which also sits on top of the engine, very close to the purple VCV. This EGR VSV looks like the one used on the vacuum modulator system but it has three hoses on it instead of two. One comes into the EGR VSV from the VCV.
What is VSV valve?
The vacuum switching valve (VSV) which controls the vacuum supply to the actuator is normally closed and passes vacuum to the actuator when it is energized by the ECU. The ECU actuates the VSV to close the valve when the throttle position is 60% or greater and engine speed is 3,900 RPM or more.
What could cause the code p0401?
Code P0401 is triggered when the EGR temperature sensor does not see enough of a temperature change when the EGR is commanded to open. These sensors tend to get a lot of carbon buildup that causes them to lose sensitivity to the heat from the EGR gases.
What does code p0402 mean?
What the P0402 code means. P0402 is an OBD-II generic code that the engine control module (ECM) has detected indicating the engine exhaust gas recirculation ( EGR ) valve is flowing too much recirculated exhaust gases when it is commanded to open the flow of gases into the intake manifold.
What are the functions of the EGR valve?
The function of the EGR valve is to recirculate small amounts of exhaust back into the combustion chambers of the engine in order to decrease the combustion temperature, thereby reducing the formation of smog-producing nitrogen oxides. EGR valves can malfunction by becoming stuck open or closed due to carbon buildup.
What does p0404 OBD code mean?
OBD-II Code P0404 is defined as a Exhaust Gas Recirculation Circuit Range/Performance NOx gases, which cause acid rain and respiratory problems, are formed when the engine’s combustion temperature is too high (2500° F). EGR systems are used to reduce the combustion temperature, thus reducing NOx formation. Aug 12 2019