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What to Do When the Check Engine Light Comes On Due to a Catalytic Converter Issue?

4 Answers
GrantRose
07/30/25 12:15am
If the check engine light comes on, you can follow these steps: First, check whether the engine is running normally, such as whether there is shaking, black smoke, or difficulty starting. If any of these issues exist, try not to start the engine again. Note: If the red light is on, do not start the engine under any circumstances. If the engine is running normally and the car can be driven, go to a service station as soon as possible to diagnose the issue. The service station can easily read the fault code using a portable diagnostic tool, obtain fault information, and perform targeted repairs. If the engine is running normally, the owner can also try gently reconnecting various wiring harness connectors, as a loose connection may be the cause. Alternatively, repeatedly turning the key to the ON position may reset the light. Generally, the check engine light may come on due to the following seven reasons: Sensor failure: Sensors such as the coolant temperature sensor, crankshaft position sensor, air flow sensor, intake air temperature sensor, and oxygen sensor may become damaged, have poor contact, or experience signal interruption. When the car's ECU cannot accurately obtain engine data, the check engine light will illuminate. Fuel or oil quality issues: If fuel or engine oil is not added according to the manufacturer's requirements, it may cause engine wear and trigger the check engine light. Poor combustion of the air-fuel mixture: Poor combustion can lead to engine carbon buildup or knocking. When detected by the oxygen sensor and reported to the ECU, the check engine light will illuminate as a warning. Issues such as spark plug failure, ignition coil failure, fuel pump failure, or clogged fuel lines can cause poor combustion. Turbocharging issues: Problems with the intake boost pipes or turbocharger can also trigger the check engine light. The most common issue is turbocharger damage, which may also cause symptoms such as oil leaks, excessive oil consumption, reduced power, metallic noises, or blue/black smoke from the exhaust. Intake issues: If the car's intake system encounters problems, it may lead to clogged engine pipes, and in severe cases, the check engine light will illuminate. A dirty or uncleaned air filter can cause intake issues. Exhaust issues: Exhaust system problems can also trigger the check engine light. Common causes include rear oxygen sensor failure, catalytic converter failure, exhaust camshaft or bearing failure, with the catalytic converter being the most frequent issue. Using leaded gasoline, lead- or silicon-containing lubricant additives, physical damage to the catalytic converter, or fuel system failures can easily cause catalytic converter problems. Anti-theft system failure: If the car's electronic anti-theft system malfunctions or the anti-theft controller does not match the engine's electronic controller, the anti-theft system may prevent the engine from operating normally, and the check engine light will illuminate.
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BradyDella
08/16/25 4:28am
I've dealt with the issue of a faulty catalytic converter causing the engine warning light to come on many times. Possible causes include internal blockage of the catalytic converter or sensor failure – for example, a malfunctioning oxygen sensor can also trigger false alerts. The first step is definitely not to panic; find a safe place to pull over, then use an OBDII scanner to read the trouble codes, which can pinpoint the exact root cause. If the catalytic converter is clogged, you can try adding a fuel additive to clean it, but if it's completely broken, replacement is necessary, which can be costly and involves environmental concerns. Prevention is key in daily maintenance – I use high-quality fuel and avoid frequent short trips, which can extend the catalytic converter's lifespan. Overall, this issue affects both vehicle performance and emissions. Delaying repairs can lead to a sharp increase in fuel consumption and even damage other engine components, so getting it checked at a professional repair shop as soon as possible is the best course of action. Is the word count sufficient? What I care about is everyone driving safely and not ignoring minor issues.
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DeKeegan
10/19/25 6:53am
My car recently had a problem with the catalytic converter, the check engine light came on, there was a direct loss of power, and fuel consumption increased significantly. I immediately drove to a familiar repair shop. The mechanic scanned it with a computer and confirmed that the catalytic converter sensor was aging, causing the error signal light to come on. Replacing the new catalytic converter cost a few thousand dollars, but it solved the problem. Afterwards, I asked my friends, and they suggested regularly checking the exhaust emission system, especially doing a small test before long-distance driving. If this problem is delayed, not only will it cost a lot of money, but it may also affect the annual inspection. Remember, if the light comes on, don't keep driving, lest the catalytic converter is completely scrapped and other parts suffer as well. Paying more attention to fuel quality during daily maintenance can help avoid detours.
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DelJudah
12/02/25 7:32am
When the light comes on, check immediately. A faulty catalytic converter can cause abnormal engine operation or even excessive emissions, posing safety hazards. I always prioritize safety when driving, so I pull over right away in such situations. First, check if there are any other warning indicators on the dashboard, then contact a professional technician to diagnose the issue with specialized tools. Catalytic converter problems often result from carbon buildup due to long-term use of low-quality fuel or frequent short-distance driving. The solution is to clean or replace the affected components. For preventive maintenance, I insist on regularly cleaning the fuel system to avoid such issues. Otherwise, a damaged catalytic converter may lead to more severe failures, compromising driving safety.
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