If the check engine light in your Mercedes has turned on, you should never avoid it, because an immense range of issues can cause this alert light to illuminate on your dashboard. Any serious problem that might have caused the check engine light to come on can impact the health of your car significantly. Further, if not repaired quickly, this can lead to critical damages and lower the car’s long-term performance. So it is important for you to understand the possible underlying causes of a check engine light.
General Causes for the Check Engine Light to Turn On
- Broken or Loose Gas Cap: When the gas cap is loose, broken, or lost, it can create issues that reduce the fuel pressure and allow fuel vapours to escape. This reduces the fuel economy and increases harmful emissions, which is terrible for your car’s health, environment, and, most importantly, your health.
- Faulty Oxygen Sensor: After the oxygen sensor undergoes exposure to hot exhaust gas for an extended period, it is recommended that you replace the oxygen sensor with an efficient one. Considering that the oxygen sensor provides the vital air/fuel mixture information to the ECU, using a defective oxygen sensor will direct the car’s system to supply disproportionate amounts of fuel to the engine. This is hazardous because an engine supplied with less amount of fuel can lead to the risk of total engine failure. Moreover, an engine supplied with an extra amount of fuel will create excessive smoke and odor.
- Faulty Catalytic Converter: Catalytic converters are part of the emissions system and are responsible for removing toxic carbon monoxide. Usually, the catalytic converters for the higher mileage cars are likely to clog with debris after a certain period. A defective catalytic converter can impact your car’s performance because it badly affects the fuel economy.
- Faulty Ignition Coil: As your car engine undergoes vibrations, the ignition coil gets damaged over time. This results in poor fuel economy, increased hydrocarbon emissions, exhaust backfiring, difficulty in starting the engine, and affects the spark plug.
- Bad Spark Plugs: The job of a spark plug is to create a hot spark to ignites the air and fuel mixture injected into the cylinders. This starts combustion in the engine and allows your car to run. Spark plugs naturally wear out and are less efficient the longer you use them. Spark plugs that are worn can cause engine misfires, reducing your fuel economy, leading to poor engine performance.
- Failing Mass Air Flow Sensor: The MAF sensor has a similar job as the oxygen sensor. They both measure the amount of air that enters the engine and ensures the proper air/fuel mixture. However, the MAF sensor is likely to become faulty as it is exposed to dirt or debris over time. Defective sensors can cause the engine to misfire. This not only results in poor fuel economy and poor performance but also can cause severe damage to the car’s engine.
The above-mentioned symptoms will cause the check engine light to turn on. There are few other possible causes, such as a vacuum leak, a dead or low battery, and emissions problems. Once the check engine light turns on, you should observe any noticeable changes and reduce the amount of driving to avoid further damage. Opt for the best solution, which is to carefully drive your car to the service center, unless you believe it needs a tow.
Hagan’s Motor Pool At Your Service
The technicians at Hagan’s Motor Pool are committed to finding the problem and repairing it right the first time. The service department 
at Hagan’s Motor Pool specialises in German auto check engine light diagnostics and repairs. As each make and model requires unique diagnostics to determine the cause for any check engine light issue, Hagan’s Motor Pool is the best fit for this task.
With a strong belief in a straightforward communication process, we provide faster results and better service for your car. You can completely count on our service members for an honest inspection and diagnosis and a fast turnaround time.
Hagan’s Motor Pool is proud to be a veteran-owned business, and we proudly offer all who have served our country a veterans discount on any repairs needed for your car.
Located at 152 Farmington Road, Rochester, NH 03867, Hagan’s Motor Pool is the go-to service center for German auto owners in surrounding areas, such as Alton, Barrington, Berwick, and Dover. If your check engine light is on, call or visit Hagan’s Motor Pool to get the best service for your car. To schedule an appointment, contact us at (603) 332-6822 or stop by our service center today.