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Emission control system

The emission control system of your vehicle is covered by a written limited warranty. Please see the warranty information contained in the Warranty & Consumer Information manual in your vehicle.

Your vehicle is equipped with an emission control system to meet all applicable emission regulations. There are three emission control systems, as follows.

  1. Crankcase emission control system

  2. Evaporative emission control system

  3. Exhaust emission control system

In order to assure the proper function of the emission control systems, it is recommended that you have your vehicle inspected and maintained by an authorised Kia dealer in accordance with the maintenance schedule in this manual.

Caution for the Inspection and Maintenance Test (With Electronic Stability Control (ESC) system)

  • To prevent the vehicle from misfiring during dynamometer testing, turn the ESC off by pressing the ESC switch.

  • After dynamometer testing is completed, turn the ESC back on by pressing the ESC switch again.

1. Crankcase emission control system

The Positive Crankcase Ventilation system is employed to prevent air pollution caused by blow-by gases being emitted from the crankcase. This system supplies fresh filtered air to the crankcase through the air intake hose. Inside the crankcase, the fresh air mixes with blow-by gases, which then pass through the Positive Crankcase Ventilation (PCV) valve into the induction system.

2. Evaporative emission control (including Onboard Refuelling Vapour Recovery (ORVR)) system

The evaporative emission control system is designed to prevent fuel vapours from escaping into the atmosphere. (The ORVR system is designed to allow the vapours from the fuel tank to be loaded into a canister whilst refuelling at the gas station, preventing the escape of fuel vapours into the atmosphere.)


Fuel vapours generated inside the fuel tank are absorbed and stored in the onboard canister. When the engine is running, the fuel vapours absorbed in the canister are drawn into the surge tank through the Purge Control Solenoid Valve.

Purge Control Solenoid Valve (PCSV)

The Purge Control Solenoid Valve (PCSV) is controlled by the Engine Control Module (ECM); when the engine coolant temperature is low during idling, the PCSV closes so that evaporated fuel is not taken into the engine. After the engine warms up during ordinary driving, the PCSV opens to introduce evaporated fuel to the engine.

3. Exhaust emission control system

The exhaust emission control system is a highly effective system which controls exhaust emissions whilst maintaining good vehicle performance.

Engine exhaust gas precautions (carbon monoxide)
  • Carbon monoxide can be present with other exhaust fumes. Therefore, if you smell exhaust fumes of any kind inside your vehicle, have it inspected and repaired immediately. If you ever suspect exhaust fumes are coming into your vehicle, drive it only with all the windows fully open. Have your vehicle checked and repaired immediately.



    Engine exhaust gases contain carbon monoxide (CO). Though colourless and odourless, it is dangerous and could be lethal if inhaled. Follow the instructions on this page to avoid CO poisoning.

  • Do not operate the engine in confined or closed areas (such as garages) any more than what is necessary to move the vehicle in or out of the area.

  • When the vehicle is stopped in an open area for more than a short time with the engine running, adjust the ventilation system (as needed) to draw outside air into the vehicle.

  • Never sit in a parked or stopped vehicle for any extended time with the engine running.

  • When the engine stalls or fails to start, excessive attempts to restart the engine may cause damage to the emission control system.

Operating precautions for catalytic converters

Catalytic converter

Keep away from the catalytic converter and exhaust system whilst the vehicle is running or immediately thereafter. The exhaust and catalytic systems are very hot and may burn you.



  • Do not park, idle or drive the vehicle over or near flammable objects, such as grass, vegetation, paper, leaves, etc. A hot exhaust system can ignite flammable items under your vehicle.

  • Also, do not remove the heat sink around the exhaust system, do not seal the bottom of the vehicle or do not coat the vehicle for corrosion control. It may present a fire risk under certain conditions.

Your vehicle is equipped with a catalytic converter emission control device.

Therefore, the following precautions must be observed:

  • Use only UNLEADED FUEL for petrol engines.

  • Do not operate the vehicle when there are signs of engine malfunction, such as misfire or a noticeable loss of performance.

  • Do not misuse or abuse the engine. Examples of misuse are coasting with the ignition off and descending steep grades in gear with the ignition off.

  • Do not operate the engine at high idle speed for extended periods (5 minutes or more).

  • Do not modify or tamper with any part of the engine or emission control system. All inspections and adjustments must be made by a professional workshop. Kia recommends to visit an authorised Kia dealer/service partner.

  • Avoid driving with an extremely low fuel level. Running out of fuel could cause the engine to misfire, damaging the catalytic converter.

Failure to observe these precautions could result in damage to the catalytic converter and to your vehicle. Additionally, such actions could void your warranties.

Petrol Particulate Filter (PPF) (if equipped)

The Petrol Particulate Filter (PPF) system removes the soot in the exhaust gas.

The PPF system automatically burns (or oxidizes) the accumulated soot in accordance with driving situations, unlike a disposable air filter.

In other words, the accumulated soot is automatically purged out by the engine control system and by the high exhaust-gas temperature at normal/ high driving speeds.

However, when the vehicle is continually driven at repeated short distances or driven at low speed for a long time, the accumulated soot may not be automatically removed because of low exhaust gas temperature. In this case, the accumulated soot may reach a certain amount regardless of the soot oxidization process, then the PPF lamp () will illuminate.

PPF Lamp stops illuminating, when the driving speed exceeds 80 km/h with engine rpm 1,500~4,000 and the gear in the 3rd position or above for approximately 30 minutes.

When the PPF lamp starts to blink or the warning message "check exhaust system" pops up even though the vehicle was driven as mentioned above, we recommend that you have the PPF system checked by an authorised Kia dealer. With the PPF lamp blinking for an extended period of time, it may damage the PPF system and lower the fuel economy.

Diesel particulate filter (if equipped)

The Diesel Particulate Filter (DPF) system removes the soot in the exhaust gas.

Unlike a disposable air filter, the DPF system automatically burns (oxidizes) and removes the accumulated soot according to the driving condition. In other words, the active burning by engine control system and high exhaust gas temperature caused by normal/high driving condition burns and removes the accumulated soot. However, if the vehicle continues to be driven at repeated short distance or driven at low speed for a long time, the accumulated soot may not be automatically removed because of low exhaust gas temperature. More than a certain amount of soot deposited, the malfunction indicator light () illuminates.

When the malfunction indicator light blinks, it may stop blinking by driving the vehicle at more than 60 km/h (37 mph) or at more than second gear with 1500~2500 engine rpm for a certain time (for about 25 minutes).

If the malfunction indicator light () continues to be blinked or the warning message "Check exhaust system" illuminates in spite of the procedure, visit a professional workshop and check the DPF system. Kia recommends to visit an authorised Kia dealer/service partner. If you continue to drive with the malfunction indicator light blinking for a long time, the DPF system can be damaged and fuel consumption can be worsen and engine durability can be worsen by oil dilution.


It is recommended to use the regulated automotive diesel fuel for diesel vehicle equipped with the DPF system.

If you use diesel fuel including high sulfur (more than 50 ppm sulfur) and unspecified additives, it can cause the DPF system to be damaged and white smoke can be emitted.

Contains Topics
Lean NOx Trap