Automotive computer knowledge (4)

1. Three main typesCarPolluted waste is unburned hydrocarbons HC, carbon monoxide CO, and nitrogen oxides.
NOx.
2. HC emissions are produced by unburned fuel during the combustion process.
3. NOx is produced by the combination of oxygen and nitridation in the high-temperature combustion chamber.
4. The oxidation catalyst can change HC and CO into carbon dioxide and water vapor.
5. The three-way catalyst can reduce NOx to oxygen and nitrogen.
6. PCV preventionCrankshaftThe exhaust gas in the box leaks into the atmosphere.
7. The PCV valve is controlled by the vacuum of the intake manifold and the spring pressure.
8. In the EGR system, when the vacuum is supplied to the diaphragm chamber above the diaphragm, the exhaust port EGR valve is opened.
9. The positive pressure EGR valve has a long-open control valve in the center of the diaphragm.This control valve is in a certain regulationThrottleThe opening is closed by exhaust pressure.

10. The negative back pressure EGR valve has a long-closed control valve in the center of the diaphragm. This valve is opened by the negative pressure pulse in the exhaust system at low engine speed.

11. There are up to three digital EGR valves operated by PCM modulesSolenoid valve.
12. The linear EGR valve has a solenoid valve controlled by the PCM module through pulse width modulation signals.
13. There is an exhaust temperature in some EGR valvessensor. It sends the voltage signal related to the exhaust temperature to the PCM module.

14. The EGR vacuum regulator (EVR) is a solenoid valve operated by PCM, which is connected to the vacuum line leading to the EGR valve.

15. Pressure feedback electronicssensor(PFE) Send a voltage signal related to the exhaust pressure below the EGR valve to the PCM module.