EMISSION CONTROL SYSTEM 7-1
SH010A1-E EMISSION CONTROL SYSTEMS (Not all models) Depending upon the market for which the vehicleis destined, the emission control system willcomprise one or more of the following emissioncontrol devices. (1) Crankcase emission control system (2) Evaporative emission control system(3) Exhaust emission control system In order that the proper functioning of the emis- sion control systems may be ensured, it isrecommended that the vehicle is inspected andmaintained by an authorized Hyundai dealer inaccordance with the maintenance schedule inthis manual.
SH000A1-E
7. EMISSION
CONTROL SYSTEM
SH010B1-E
1. CRANKCASE EMISSION CONTROL SYSTEM
The positive crankcase ventilation system is employed to prevent air pollution caused byblow-by gases being emitted from the crankcase by introducing fresh air to the crankcase throughthe air cleaner where this mixes with blow-bygases and then passes through the PCV valveinto the intake manifold from where it subse-quently enters the combustion chamber and isburned.
SH010D1-E
3. EXHAUST EMISSION CONTROL SYSTEM The exhaust emission control system is a highlyeffective system which controls exhaust emis-sion while maintaining good vehicle performance.
SH010C1-E
2. EVAPORATIVE EMISSION CONTROL SYSTEM
The Evaporative Emission Control System is designed to prevent fuel vapours from escapinginto the atmosphere through the fuel tank venti-lation system.Whilst the engine is not running, fuel vapours generated inside the fuel tank are absorbed and stored in a charcoal canister. When the engine isstarted, the vapours stored in the canister aredrawn into the induction system through thepurge control solenoid valve and are subse-quently burned.The purge control solenoid valve is controlled bythe ECU; when the engine coolant temperatureis low or the engine is idling, the purge controlvalve is closed and fuel vapours remain stored inthe canister. Under normal running conditionswhen the engine is warm, the valve opens andthe vapours are drawn into the inlet tract andsubsequently burned in the combustion cham-ber. SH020A1-E CATALYTIC CONVERTOR OPERATING PRECAUTIONS Hyundai Coupe models are fitted with catalytic convertors which require special operating con-siderations. The catalytic convertor serves tooxidize certain noxious elements of the exhaustgases leaving the engine to reduce the level ofpollutants emitted from the vehicle and, providedthat care is exercised to prevent damage, thecatalyst will operate efficiently for the life of thevehicle.It is of the utmost importance that the followinginformation is read and understood by the ve-
7
Catalytic Converter
SSA7020A
EMISSION CONTROL SYSTEM
7-2
hicle operator in order to prevent operational problems arising from damage to the catalyst.Damage to the catalyst will result if contamina-tion occurs through the use of leaded fuel. Whilstthe vehicle is fitted with a reduced diameter fillerneck to prevent charging of the fuel tank with aleaded fuel pump nozzle, it is possible that theuse of funnels or jerry cans will permit leaded fuelto be introduced into the fuel tank.The catalyst is intolerant of unburnt fuel andtherefore if an engine misfire condition exists,damage to the catalyst will occur. It is imperativethat if a misfire condition develops, the vehicle isimmediately presented to a Hyundai dealer forrectification. Similarly, the practice of certainignition system diagnosis procedures which in-volve inducing a misfire (cylinder power balancetests for example) may result in catalyst dam-age.For these reasons, it is advisable that the ex-haust gas emission be tested at each routineservice with a gas analyzer having a Hydrocar-bon measuring facility to ensure continued reli-ability of the catalyst.Push or tow starting of the vehicle is to beavoided since unburnt fuel may be enter thecatalyst and result in damage. (Note, it is impos-sible to push or tow start a Hyundai modelequipped with fuel injection since the fuel pumpsafety interlock will prevent the pump from oper-ating under these conditions).Operation of the catalyst involves extremely hightemperatures being attained within the catalyticconvertor, and although the convertor is fitted
with heat shields, it is important that the vehicleis not parked over combustible or volatile mate-rial which may result in fire.If the above precautions are not adhered to andthe catalyst becomes inoperative, the resultantincrease in core temperature will result in a "meltdown" where the catalyst core will melt andsubsequently may block the exhaust system.Due to the fragile nature of the catalyst element,it is important that damage does not occur whenthe vehicle is raised by means of a garage jack.Care must also be exercised to avoid drivingover road hazards or debris which may causedamage to the catalyst element.
