2018 Kia Forte5 Has A Check Engine Light

Common Causes of the Check Engine Light in Your 2018 Kia Forte5 and How to Resolve Them

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Reviewed by
Devin Cabugcal
Written by RepairPal Car Genius
Updated January 14, 2025
0%
40% chance it's the
Emissions System
0%
60% chance it's
Something else
The most common reasons a 2018 Kia Forte5 has a check engine light are an emissions system component, a sensor, or a catalytic converter.
  • Emissions System: A faulty emissions system component, such as an oxygen sensor or EGR valve, can lead to increased emissions and trigger the check engine light.
Proper diagnosis will determine the exact cause of your symptom, saving you money on unnecessary repairs. The diagnostic experts at RepairPal Certified shops have the right tools and experience to solve any symptom.

How much does it cost to fix a 2018 Kia Forte5 has a check engine light?

Common Repairs

The total repair cost will vary based on the condition of your vehicle and the number of repairs needed to fix your symptom. Proper diagnosis will save you money by finding the exact repairs needed to fix your car right the first time.

A faulty oxygen sensor is one of the most common causes of a check engine light. Symptoms may include a decrease in fuel mileage, hesitation or misfiring from the engine, rough idling or even stalling. A faulty sensor may cause the vehicle to fail an emissions test.

Any time there is an emissions fault the check engine light will be displayed. The purpose of the check engine light is to inform the driver that an emission related fault has been found, and that there are on-board diagnostic (OBD) trouble codes stored in the powertrain or engine control module. Additionally, since the emissions systems are so intertwined into engine control and transmission control systems, symptoms may include nearly any sort of drivability concerns. This may include harsh shifting, failure to shift, hesitation on acceleration, jerking, engine failure to start or run, loss of power, or any number of other drivability issues.

Due to the nature of electrical systems on modern vehicles, the range of problems these can cause are nearly limitless. However, there is a way to categorize them in two ways. Permanent and intermittent problems. Permanent problems appear and remain. This may be the vehicle will not start, the radio does not work, or the door chime will not turn off among many, many others. These problems are more straight-forward to diagnose since they present themselves at all time. This means there will always be a fault to find. Intermittent electrical problems, however, can be difficult or impossible to locate, since they appear then disappear without warning. The best case scenario for an intermittent issue is when replicating the problem is easily accomplished and understood. This allows a technician to make an issue semi-permanent, allowing them to find the fault. Other issues that come and go without warning and cannot be replicated on demand must occur when the technician is servicing the vehicle, otherwise there is no problem to correct. It is most important to understand that electrical system faults always require inspection, and can include the vehicle working in any manner, or not working at all.

Like we noted in the last section, general diagnosis symptoms are the most vague of the bunch. There are several diagnostic spectrums, electrical diagnosis, drivability diagnostics, engine diagnostics, transmission diagnostics, and the list could continue for about 5 or 10 more spectrums of diagnostics. The most important take-away here, is that general diagnostics are diagnostics that have no other spectrum in which they fit, or the problem is unknown. This means that any vehicle left outside of a repair facility with the keys and an authorization to perform diagnosis will be diagnosed under the general diagnosis spectrum.

When the Check Engine Light comes on, you may experience engine performance issues such as poor acceleration, rough idling, or an engine that won't start. In some cases, no abnormal symptoms will be experienced. Other systems like the transmission or ABS can cause the Check Engine Light to illuminate and lights for those systems can come on at the same time. Similar lights may say "Check Engine Soon", "Malfunction Indicator Light" or just "Check". In rare case the engine can overheat.

What are the initial diagnostic steps to take for a check engine light on a 2018 Kia Forte5?

When faced with a check engine light on your 2018 Kia Forte5, it's essential to adopt a systematic diagnostic approach. Start by checking the gas cap; a loose or damaged cap is a common culprit that can easily trigger the light. Next, take a moment to observe your dashboard gauges for any unusual readings, as these can provide clues about underlying issues. Inspect the engine bay for any visible damage to wires, hoses, or connectors, as physical wear can lead to malfunctions. If these initial checks do not resolve the issue, using an OBD-II scanner is a crucial next step; it will help you retrieve the specific error code associated with the check engine light, guiding you toward the problem's source. Always consult your owner's manual for detailed information on the error code and recommended actions. If the problem persists or seems too complex, don’t hesitate to seek professional assistance to ensure your vehicle is safely and effectively diagnosed. By following this methodical approach, you can efficiently identify and address the cause of the check engine light, potentially saving time and money in the process.

What are the common problems that could cause the check engine light to illuminate in a 2018 Kia Forte5?

When the check engine light comes on in your 2018 Kia Forte5, it can be concerning, but understanding the common problems that may trigger this warning can help you address the issue effectively. One frequent culprit is a loose gas cap, which can easily be checked and tightened to potentially resolve the light. Another common issue is a faulty oxygen sensor, which affects fuel efficiency and may require replacement if diagnosed. Problems with the catalytic converter can also lead to the check engine light illuminating, often indicating a need for repair or replacement. Additionally, worn-out spark plugs can impact engine performance, while a malfunctioning mass airflow sensor can disrupt the air-fuel mixture, both of which may trigger the light. Ignition coil problems and engine misfires, often linked to bad spark plugs or coils, are other potential causes. If you encounter the check engine light, it’s wise to conduct a thorough inspection or consult a mechanic to accurately diagnose and resolve the underlying issue.

How urgent is it to address the check engine light in a 2018 Kia Forte5?

When the check engine light illuminates in your 2018 Kia Forte5, it signals a potential issue that requires immediate attention. Ignoring this warning can lead to serious consequences, including extensive engine damage and costly repairs. The check engine light often indicates problems with the engine or emissions system, which, if left unaddressed, can worsen over time, resulting in decreased fuel efficiency and compromised vehicle performance. For DIY enthusiasts, it’s essential to understand that while some issues may seem minor, they can escalate quickly, posing safety risks on the road. Therefore, it is advisable to use an OBD-II scanner to diagnose the issue yourself, allowing you to identify the specific trouble codes and take appropriate action. However, if the problem appears complex or beyond your expertise, seeking professional assistance is crucial to ensure the safety and reliability of your vehicle. Addressing the check engine light promptly not only protects your investment but also enhances your driving experience.

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2018 Kia Forte5 Check Engine Light: Causes & Solutions