Operating principle
To reduce emissions of harmful substances (CO, HC, NOx) with exhaust gases, the engine control system has been modified with the addition of special elements. The changes affected the combustion chamber, intake manifold, camshaft and ignition system, which form the main control system.
These systems have been combined into an effective system that manages emissions reduction while maintaining good overall vehicle drivability and fuel economy.
MFI fuel injection system
The MFI fuel injection system uses signals from a heated oxygen sensor to adjust the control modes of the fuel injectors mounted in the intake manifold for each cylinder, providing precise air/fuel ratio control for reduced exhaust emissions.
This ensures the release of exhaust gases of a certain composition, which can be further purified in a three-way catalytic converter.
The three-way catalytic converter is designed to convert three harmful substances (hydrocarbons (HC), (2) carbon monoxide (CO) and (3) nitrogen oxides (NOx) into safe substances.
The MFI system operates in two modes:
1. In an open loop, when the composition of the fuel-air mixture is regulated by a program embedded in the engine control unit.
Material was obtained from an official resource: HyundaiBook.ru
2. In a closed loop, when the composition of the fuel-air mixture is regulated based on information from the oxygen sensor.
Troubleshooting
| Sign | Probable cause | Method of elimination |
| The engine does not start or starts with difficulty | Vacuum hoses are disconnected or damaged | Repair or replace vacuum hoses |
| Malfunction of the fuel vapor recovery system valve | Repair or replace the evaporative emission control valve | |
| Unstable engine operation at idle, up to and including engine stalling | Vacuum hoses are disconnected or damaged | Repair or replace vacuum hoses |
| Malfunction of the crankcase ventilation valve | Repair or replace the PCV valve | |
| Malfunction of the fuel vapor recovery system valve | Repair or replace the evaporative emission control valve | |
| Increased oil consumption | Clogging of the forced crankcase ventilation system | Check and, if necessary, clean the components of the positive crankcase ventilation system |