Anytime the check engine light comes on, it indicates something needs your attention. At a minimum, it could mean a loose gas cap or extensive issues like failed sensors, wiring, or connectors. Several options are available to read Check Engine Light codes, ranging from DIY reading to professional diagnostics by trained auto repair.
In this article, we will help you understand these options in detail, why your CEL goes on, and the potential causes of the problem. If you recently bought a code scanner, we will cover how to use it to read codes from the CEL.
Lit or Flashing Check Engine Light
Is your CEL steady or flashing? A steady Check Engine Light has two explanations, a signal indicating something is wrong, or the vehicle's ECU is not receiving information from that sensor. You may receive multiple signals from different sensors, which means a bigger problem.
Notwithstanding, you can still drive with the light on. Make sure to visit an auto repair shop as soon as possible to check for further problems. Should the Check Engine light start flashing, pull over and get professional service. Your vehicle needs urgent attention and could have imminent damage if you continue driving.
You have two options, visit an auto repair shop or do it yourself. All you need for DIY checking is an OBD2 reader. OBD2 codes, also known as trouble codes, tell you what is wrong with your vehicle. The machine transmits a signal from the vehicle transmission to the ignition.
The OBD2 port is under the steering column and reads your car’s error codes. Where you need a code reader, you may research websites like these to learn what is wrong. Check vast reasons with hundreds of potential codes in onboard computers for lighting Check Engine light.
Auto Repair Shop
Nevertheless, taking your vehicle to a professional automotive shop is the best option. These shops invest thousands of dollars in diagnostic equipment and take time to train the use of such equipment. Experienced mechanics will handle the inspection with 100 percent accuracy and determine precisely why the CEL came on.
DIY check may show you the reason but not why it happened. Here is where professionals come in. Auto shops have ASE-certified technicians armed with high-value diagnostic equipment. Even the most avid DIYers need the help of professional diagnostics.
Visit your Local Mechanic
Suppose you have established an excellent relationship with your local mechanic. They will scan your car for free. Further, a mechanic will give you more detailed information than you could get. It is great to have a professional mechanic who understands your vehicle better.
Once you build good relations with them, they are likely to give you free diagnostics since they know you and know you will use their services should you need repairs. If your diagnostics take longer than expected, do not expect free service.
Visit your Dealership
Your vehicle dealership will give you detailed diagnostics for issues included in the warranty. The dealership will likely have state-of-the-art diagnostic equipment that local mechanics or auto shops don’t and will provide you with detailed information. You may have to pay extra money for advanced diagnostics.
Why Your Check Engine Light is on
Oxygen sensors have failed
A car is fitted with oxygen sensors to measure the amount of unburned oxygen in the exhaust system. The sensors will show you the air-fuel mixture burnt off during combustion. Moreover, these sensors work at more than 800 degrees temperature, which makes them prone to failure. Oxygen sensor replacement is required after approximately 80,000 miles.
Before concluding the oxygen sensor is faulty, it is essential to note the multiple engine codes. Failure to address the sensor damage may cause your engine to burn more fuel than needed. Additionally, you lose fuel economy, which results in a few miles per gallon. The failure could ultimately extend to damaged spark plugs and catalytic converters.
Loose or damaged gas cap
Your gas cap could be missing or damaged on minor CEL concerns. A gas cap is an additional part of a sealed evaporative emissions system, which recirculates gasoline vapors from your gas tank. A damaged gas tank keeps airtight and thus monitors valves, and system lines are closed.
Check Engine Light will go on if you leave your gas cap off accidentally. Experts grouped these errors as either small or large leaks. The problem could be the gas cap, fittings, plastic recirculation lines, or connectors.
Failure to address the gas cap issue could lead to lost fuel through evaporation and malfunctioning of the recirculation system. The CEL will continue lighting until you fix the problem.
Relevant:Choosing the Right OBD2 Scanner for Your Needs.
Malfunctioned catalytic converter
A catalytic converter is an essential car part of promoting eco-friendliness. It superheats hydrocarbons and other tailpipe emissions like carbon dioxide. A vehicle is fitted with additional oxygen sensors downstream, which monitor the converter's performance. With trouble codes, you are likely to face a catalyst efficiency issue.
Notably, a catalytic converter does not fail on its own. An oxygen sensor replacement or replacing the converter will not solve the problem. Further, you are likely to experience another failed converter. Converter issues may be blown head gasket or force-burned coolant vapor in the exhaust. If you do nothing about it, you may experience the following issues;
- Reduced vehicle performance and lower fuel economy
- Failed vehicle emissions test, or
- Worse problems and ultimate engine failure
Mass airflow sensor
MAF sensor in a vehicle measures the amount of air entering the engine. This determines the amount of fuel needed to run the engine effectively. CEL may go on in case of a leak before or after the MAF sensor in the intake tract.
A mass airflow sensor, MAF, is triggered by the tiniest particles of dirt, water vapor, or oil. At the least, clean the sensor to fix the issue or replace it in the worst scenarios. Check the intake ducting for leaks, rips, or damage before replacement.
How to use an OBD2 Scanner
You can pay a mechanic a lot to read car error codes or do it yourself. First, plug the OBD2 scanner into the OBD2 port. Once plugged in, switch it on if it is battery-powered. Some use power from the OBD2 port to switch on. Since each OBD2 scanner is different, there are various ways to read your car’s error codes. How to Read OBD2 Codes?
Basic scanners will show you the error code and let you research what the code means. Moreover, advanced scanners will tell you the exact code and its meaning. Notwithstanding, you will need more diagnostics to fix the errors.
If you have your own scanner, diagnose your issues and save some bucks. Sometimes, you may need to bring it in and pay for detailed diagnostics. If you need a scanner, Ancel sells all OBD2 scanners through their official website.