Volkswagen Check Engine Light

What Causes a Volkswagen Check Engine Light?

Nobody likes to see the Volkswagen check engine light turn on in their vehicle. For one thing, it indicates that something is wrong with the vehicle; for another, it doesn't tell you what exactly is wrong. Hundreds of issues can trigger a Volkswagen Atlas check engine light.

The causes of a check engine light coming on range from serious problems that need to be resolved immediately to small issues such as the Volkswagen gas cap check engine light that simply means you need to tighten the gas cap.

When a Volkswagen Jetta check engine light comes on in your vehicle, the best step to take is to contact our Volkswagen service department for a check engine light diagnosis and reset appointment.

What Do VW Check Engine Light Codes Mean?

There are numerous reasons for a Volkswagen Passat check engine light. If the check engine light in your new VW has turned on, contact an authorized VW service department for assistance. The common causes of a VW check engine include:

• A loose, missing, or damaged gas cap
• A low or expired car battery
• Bad spark plugs
• O2 sensor failing
• Fuel and air mixture issues
• Faulty mass airflow sensor
• Emissions controls and exhaust issues
• Transmission problems
• Ignition system faults

When you schedule a check engine light Volkswagen Tiguan appointment, our team will connect an engine diagnostic scanner and OBD2 code reader to your vehicle's onboard computer. Once the scanner reads your vehicle's ECM and determines which of the VW check engine light codes activated the check engine light, a member of our professional VW repair team will resolve the issue, reset the check engine light, and get you on your way.

EPC and Check Engine Light Volkswagen Causes

A check engine light can be one of the more stress-inducing Volkswagen dashboard warning lights because there are so many causes of a VW check engine light. If a temperature or oil pressure warning light turns on, you know what it means, but there are many causes of a check engine light. Let's look at some of the causes of a VW check engine light mentioned above in greater detail.

A loose, missing, or damaged gas cap is one of the most common causes of a check engine light. People are in a hurry after they fill up at the gas station and leave without securely tightening the gas cap. This causes a sensor to detect a pressure issue and triggers a check engine light. It's also possible that the gas cap seal is worn out or damaged and hasn't created a secure seal, which is causing fuel evaporation to trigger a check engine light.

A low or expired car battery can also trigger a check engine light. The electrical systems in your vehicle rely on the battery. If the battery is beginning to fail or expire, the low voltage can trigger a check engine light so you have time to replace the battery before you're stuck with a car that won't start. This is one of the reasons why you should always pay attention to a check engine light, as it could determine whether you can even operate the vehicle or not.

Bad spark plugs will cause a check engine light to come on when the air/fuel mixture is off. Spark plugs deliver the spark that ignites the fuel and air mixture and causes the combustion in your car's internal combustion engine. When spark plugs and spark plug wires fail, the vehicle's power and performance will be reduced, and a check engine light may trigger. Bad spark plugs are inexpensive and easy to repair. Still, if proper maintenance is postponed, worn spark plugs can damage the O2 sensors, catalytic converter, and ignition coils, which are more significant and costly repairs.

The O2 sensor failing or fuel and air mixture issues will cause a VW check engine light because either of those problems can lead to faulty exhaust emissions and excess carbon dioxide. A bad O2 sensor can trigger a check engine light, which is why a car with a check engine light is an automatic fail in a SMOG test. The check engine light needs to be reset, and the VW check engine light cause needs to be resolved before a vehicle can pass an emissions test.

The mass air flow sensor or MAF measures the amount of air entering the engine and determines how much fuel is needed from the fuel injectors to create the ideal air/fuel mixture. The air/fuel mixture is what sparks and ignites from the spark plugs to power the engine. The smoke from these miniature explosions goes out of the exhaust pipes. When the mass airflow sensor fails and needs to be replaced, it can cause a VW check engine light to come on. If your car has a fully charged battery and is having trouble starting or a rough idle is present, the mass airflow sensor may be on its way out. We recommend scheduling a service appointment at our VW repair shop and brake center.

Emissions controls and exhaust issues from a bad catalytic converter will trigger a check engine light. The catalytic converter is an essential emissions component that turns carbon monoxide into carbon dioxide. A bad catalytic converter is harmful to the environment and the air we breathe. Consequently, a faulty catalytic converter will turn on the check engine light to ensure the vehicle does not pass emissions/SMOG testing and can only be registered once repaired. A faulty catalytic converter will also impact engine performance and fuel economy.

Transmission problems will cause a VW check engine light to come on if the transmission sends a code to the car's ECM. The transmission regulates power to the wheels at all speeds. Like changing gears on a bicycle, a car's transmission shifts gears as you accelerate and decelerate to transfer appropriate power to the wheels so the engine is not strained. If a problem with the gears or a transmission fluid leak is present, a check engine warning light may appear.

The best step to take when a check engine light comes on is to immediately schedule an appointment for your vehicle with an authorized VW repair and oil change center for a check engine light appointment.