4 Common Reasons the Check Engine Light Comes On There are many, many reasons that the check engine light may come on in you car, truck or SUV. A loose fuel cap is one of the most common reasons why the check engine light turns on. Your email address will not be published. 5 Reasons Your Check Engine Light May be On 1 Failed Oxygen (O2) Sensors Your oxygen sensor measures the amount of unburned oxygen in your vehicle’s exhaust system. After refueling, do not forget to tighten your gas cap in place. Related: Guide: Maintaining Your Car Radiator. He is very knowledgeable and wiling to take the time to explain things in detail with no jargon. The mass airflow sensor tells the car’s computer to add the proper amount of fuel based on the air coming through to the engine. Is it safe to drive the car with the check engine light on? This tends to happen quicker with fuel and exhaust system sensors, which are exposed to hot gases and carbon deposits. But if the light remains on after these two steps, it’s time to take it in. Still, anytime a CEL illuminates on your dashboard, it is something that should be taken seriously. Other signs of a failing O2 sensor include: What’s the solution to this problem? It results in low fuel and performance. I will sure be using him for future services. The most popular service booked by readers of this article is Oil Change. We worked on a Ford truck once that triggered the Check Engine light every time it rained. Replace the catalytic converter. A clogged catalytic converter can cause poor fuel mileage, engine misfiring, and even lead to internal engine damage if not replaced. The cap is a crucial part of a car’s fuel delivery system. Reasons why your check engine light is on include: Loose Gas Cap This is the first item you should check. To fix it, you should get it tightened, or replaced if … On top of not starting, other symptoms of a failing air flow sensor include: How to fix a mass air flow sensor issue? That kind of stuff. Most of the time, replacing the gas cap can solve the problem. He too will show you if he finds a problem with the vehicle so you can see for yourself. Once the code is suspected, you can locate the part and finally remove and replace it. When your car's check engine light illuminates your dashboard, it's usually accompanied by a sinking feeling in the pit of your stomach. They can determine whether the light is caused by a damaged MAF sensor or it simply needs to be cleaned. © Usually, if this is the case, your oil light will also appear. When this happens, it will create an error code and trigger the CEL. If your car will crank over but not light-up, this is probably the source. Whether that is a continuous monitor like misfires, or engine timing, or non continues monitor like the catalyst or the EVAP system, or air fuel ratio. Chevrolet Impala - Oil Change - Dallas, Texas. Firstly, check your gas cap. When it does, you can expect to see the Check Engine light. 2. Once you fix your part/condition, the check engine light will automatically shut itself off. People often end up panicking. Rancho Cucamonga, Ontario, Fontana and Inland Empire drivers should stop by Mercedes-Benz of Ontario to have a Mercedes-Benz Master-Certified technician diagnose your vehicle and have your gas cap check engine light … This is the most common reason a check engine light comes on. It’s an easy fix, too. An O2 sensor failure will typically cause a vehicle to fail an emissions test in most US states. When the electrical harness is loose, frayed, damaged, or exposed, it can send a signal to the ECU and mimic a mechanical problem. The problem is that the issues can range from minor annoyances to those requiring immediate repair. More signs of a failing catalytic converter are: How to fix this issue? It is considered best practice to replace all O2 sensors at the same time. There’s the check engine light is off. Fast, free online quotes for your car repair. The 5 Most Common Causes Of A Check Engine Light. A broken or loose gas cap, Lousy spark plugs & wires, Oxygen sensors. Prevention is better than cure. Save my name, email, and website in this browser for the next time I comment. If the gas cap is damaged or not sealed properly, the chances are that you end up losing fuel through evaporation. An oxygen sensor reads the air and fuel mixture and lights up … The ‘check engine’ light is the most common. Gas cap is loose: Tighten the gas cap. He does an awesome job with every service request to my vehicle. The codes are some generic diagnostic codes and not model-specific. Then make sure it’s seated in place. There are so many possible reasons for the check engine light to come on, so using a reader to retrieve the on-board diagnostic (OBD) codes can be helpful when the problem is not immediately evident. I say this because he was only supposed to change the oil and filter but I told him about a noise I keep hearing in the suspension. The gas caps are nothing but used to seal the fuel system of the car. Please see our, Mitsubishi Galant - Oil Change - Snellville, Georgia. Simply access the gas cap, remove it, and replace it. If the converter is not working correctly, it might lead to poor engine performance. When this happens, don’t wait or assume it will just go away. Our certified mobile mechanics perform over 600 services, including diagnostics, brakes, oil changes, scheduled mileage maintenances, and will come to you with all necessary parts and tools. The gas caps are nothing but used to seal the fuel system of the car. What can be done to fix this? Here are a few steps to fix the check engine light: In the end, do not forget to erase the code from the OBD reader. Believe it or not, the most common reason the CEL will light-up is due to a poor electrical connection from the ECU to the sensor. Mazyars what can I say the consummate professional. A check engine light is a malfunction indicator lamp and consists of a computerized engine-management system. © Copyright 2020, howtruck.com All Rights Reserved. Broken, missing, or a loose gas cap are some of the most common reasons behind the check engine light. The next step is to scan the codes as it will be displayed in the OBD reader. Secondly, try reducing the speed and load. If your check engine light is on, there’s a good chance it’s for one of these 10 reasons. Is it possible that the check engine light turns off itself? While it’s often assumed that the check engine light (CEL) is an indication of a major mechanical issue, this isn’t always the case. Required fields are marked *. Follow these easy steps to resetting your check engine light, and you should be good as gold. Great communication skills as well . Oxygen sensor needs replacing. But panic is not a solution. Common causes of a flashing or blinking check engine light The check engine light is most likely to blink if there’s a severe constant problem, like an occurring ignition misfire, injector or a temperature sensor problem, that are an essential part of the engine’s running. To many professional mechanics, a professional mechanic first light on spark and... That should be good as gold Thanksgiving and completed the full service oil Change within one hour: how this! Failed some type of problem if he finds a problem and replace.... 2001 911 turbo several times within one hour loose or cracked, one. And the issue will get resolved of issues of varying degrees of severity the necessary checks, visit nearest! 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