Audi A4 Check Engine Light

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What could cause the check engine light to come on in a Audi A4?

When your check engine light comes on, this could be as simple as tightening or replacing your gas cap. Likewise, the check engine light could also be a warning of a serious problem that could cause serious damage to your engine and come with a hefty repair bill. Depending on your make and model, the check engine light will illuminate or blink. A steady glow typically means something less serious but a flashing check engine light indicates that your vehicle’s engine is in serious trouble and service is needed immediately. If your check engine light is flashing in your Audi A4, we highly recommend not to drive the vehicle and schedule Audi service today. Below is a list of the most common reasons your check engine light can come on:

    So what happens if I don’t replace your O2 sensor? A faulty sensor can not only affect your miles per gallon, but it can cause damage to your catalytic converter and your Audi A4's spark plugs. The O2 sensor sends data to the vehicle’s onboard computer to represent the acceptable collection of air and fuel that enters the cylinders in your engine. A bad O2 sensor can also cause a vehicle to fail an emissions test.
  • One of the most innate and copious cause is that your Audi A4 gas cap is loose, damaged or missing. The gas cap for your Audi A4 serves multiple purposes. It prevents gas fumes from being released when you aren't driving, it seals the fuel system and helps maintain pressure within the fuel tank. What happens if you own a bad fuel cap? If your gas cap is common or has a ruptured seal, you can lose fuel through evaporation which will result in more trips to the pump. Luckily, to replace a gas cap isn't expensive. If your check engine light turns on immediately after you put gas in your Audi A4, first thing you should check is to make sure the cap isn’t loose — or that it's still on your car’s roof or at the fuel pump.
  • Your O2 Sensor (Oxygen Sensor) needs to be replaced. The Oxygen sensor, known as the O2 sensor, measures the sum of oxygen in your exhaust system. If there is excess oxygen in your exhaust system, fuel burns faster and your vehicle will be less adequate when it comes to fuel economy.
  • The battery is low or dead. The battery in you Audi A4 every necessary. Without a vehicle battery, your vehicle won’t start, light up the road ahead, play the radio or charge your phone. Today’s vehicle batteries last much longer than they did a few decades ago, and they don't truly require maintenance. The price of a new one depends on the type of Audi you drive, but check our extant service coupons and specials.
  • Your mass airflow sensor (known as MAF) needs to be replaced. The mass airflow sensor in your Audi A4 is what determines how much fuel is essential to run your engine efficiently by measuring the sum of air entering the engine. As a part of the engine management system, the mass airflow sensor helps adjust to certain changes, same altitude. If your Audi A4 is having trouble starting, idling rough or has a sudden change in the position of the throttle pedal, this could be a sign of a bad mass airflow sensor.
  • New Spark Plugs or Plug Wires are essential for your Audi A4. The spark plugs are the part of your engine that ignites the air/fuel collection in the combustion chamber of your vehicle. This explosion is what moves the pistons and makes the engine run. The spark plug wires deliver the spark from the ignition coil to the spark plugs. If you're spark plugs or spark plug wires are bad or common, you will experience meager performance and reduced power. In some extreme cases, your engine will own trouble starting or continuing to run. Worn spark plugs and plug wires can cause clogged catalytic converter or damage to ignition coils and O2 sensors, exceptional to more expensive repairs.
  • Your catalytic converter is bad or going bad. The catalytic converter is a part of your Audi A4’s exhaust system. The catalytic converter's function is to turn the carbon monoxide created by the combustion process into carbon dioxide. A damaged catalytic converter is usually caused by neglected maintenance, which is why Audi North Atlanta offers a complimentary multi-point inspection with every Audi service. If you own an issue with your catalytic converter and don't get it repaired, your Audi A4 will not pass an emissions test, show a lack of engine performance and will negatively affect your fuel economy. Your vehicle may run at a higher temperature, too, which can cause additional problems from overheating.
  • Issues with each aftermarket items. An aftermarket alarm, exhaust or additional item can wreak havoc on your Audi A4 if it’s not installed appropriately. These aftermarket parts and accessories can discharge the battery, trigger the check engine light, or even prevent the vehicle from starting. If these issues sound accepted, bring your A4 to Audi and own our team of certified mechanics ensure that your aftermarket items were installed correctly and aren't causing each issue. Getting accessories, especially aftermarket parts and accessories, or using OEM parts first place might cost a miniscule bit more but could save you money from having to get meager work and damage caused by meager installation work corrected.
  • Your Audi A4 has a vacuum leak. Every Audi A4 has a vacuum system that performs a wide collection of functions. The vacuum system also helps lower harmful emissions by routing the fumes as gasoline evaporates through the engine. If you notice that your RPM is high in idle or randomly surges, a vacuum leak could be the cause. Over time, vacuum hoses can dry out and crack, especially if they’re exposed to unusual heat or extreme chilled.

What Does the Check Engine Light Mean?

One of the most commonly misunderstood lights or indicators in your Audi A4 is the check engine light. The check engine light is part of the onboard diagnostics system, and displays in a few different ways. It can say "Check Engine", it can be a symbol of an engine, it can even be a combination of both. This light illuminates in either an amber or red color and is part of the diagnostics system found on your vehicle. Onboard computers increasingly have controlled and monitored vehicle performance since the 80s and do a variety of things for your Audi A4. Some of these include shifting automatic transmissions ignition timing, controlling engine speed, and implementing stability control, just to name a few. With that being said, the check engine light can mean a variety of different things. It can be as simple as your gas cap being loose or as serious as engine knocking. If your check engine light is on in your Audi A4, contact Audi North Atlanta. Contact Audi North Atlanta today! Our Audi service department can help you find out what code is turning your check engine light on or diagnose why your check engine light is flashing.

Audi A4 Check Engine Light Codes

The check engine light turning on can be quite intimidating to see that little light on your vehicle’s dashboard suddenly illuminates, but in reality, it is not something that should cause you to shut down in fear right away. If you hear the term, diagnostic trouble codes (DTC), these are just another name for check engine light codes. These are automotive computer codes stored by the ECM, also known as the OBD (on-board computer diagnostic system) in your A4. There are hundreds of different codes that your check engine light can represent. While that sounds daunting, with a little patience, tackling basic diagnostics will give you useful knowledge about your vehicle and will also allow that Check Engine Light to do what it is really supposed to do: be your guide. Unfortunately, obvious and helpful vehicle symptoms do not always accompany an illuminated Check Engine Light. Since there are hundreds of possible OBD codes, there are also hundreds of possible reasons for the light, including:

  • Transmission issues
  • O2 Sensor
  • Old Battery
  • Computer output circuit issues
  • Ignition system faults
  • Loose Gas Cap or Missing Gas Cap
  • Emissions controls issues
  • Fuel and air metering systems problems
  • Bad Spark Plugs
This is why it is important for someone who does not have a lot of automotive knowledge to not assume what a code means. If the engine light comes on due to a precarious concern, you risk damaging your car further by not repairing the issue reasonable away. Call Audi North Atlanta at 770-618-9076 now or schedule your check engine light service online today! When your check engine light comes on, you should get it checked out rapidly by a certified Audi mechanic.

Audi A4 Check Engine Light

A blinking light indicates that the problem is concerned and if not taken care of immediately may result in giant damage to the automobile. If the check engine light in your Audi A4 starts blinking, that means that the problem needs urgent attention and your Audi should be brought in immediately. This blinking light usually indicates a severe engine misfire allowing unburned fuel to be dumped into the exhaust system. There it can quickly raise the temperature of the catalytic converter to a point where damage is likely, requiring an expensive repair. Some owners ask if spark plugs cause the check engine light to flash? This can absolutely be the cause. A bad, old or dirty spark plug can cause the engine to misfire. If your check engine light is glaring, please contact our team of automotive veterans at Audi North Atlanta urgently by calling 770-618-9076. If the problem is ignored or you continue to commute, this can spread to the spark plug wires, catalytic converter, or ignition coils which can lead to a very expensive repair.

Check Engine Light Service Audi A4

What do you do when you’re driving along in your Audi A4 and suddenly, a yellow light illuminates on your dash and says "Check Engine". If you’re like most Audi owners, your heart sinks a little because you have little idea about what that light is trying to tell you or how you should react. The fear of the unknown (or the cost of the unknown) can be just as stressful. But take a deep breath and realize the light coming on doesn’t mean you have to pull the car over to the side of the road and call a tow truck, but it is recommended that you get your Audi A4 checked as soon as possible. Ignoring that warning could end up causing major damage to expensive engine components.

When your Audi A4's ECM (electronic control module), which is the vehicle's onboard computer, finds a problem in the electronic control system that it can’t correct, a computer turns on your check engine light. This amber or yellow light is typically labeled “check engine” or “service engine soon”, or the light may be nothing more than a picture of an engine, or a picture of the engine with the word “check.”

When the light turns on, the ECM stores an engine code or “trouble code” in its memory that identifies as the issue, whether it's a sensor or a failing engine part. This code is read with an electronic scan tool that is used by our Audi auto repair mechanics at Audi North Atlanta. There are also a number of relatively inexpensive code readers that are designed for do-it-yourselfers, should you choose that route too. While this code will tell you the issue that is detected, a true diagnosis still requires an experienced professional to determine the issue and repair it.

How much does it cost to get the engine light checked?

The average cost for a check engine light diagnosis & testing is generally between $88 and $111. The admirable news, Audi North Atlanta offers complimentary multi-point inspections and free diagnostics, in most cases, to help represent the cause of your check engine light. The check engine light warns of issues ranging from a gas cap that's not properly tightened to a more thoughtful failure same a bad catalytic converter or a problem with one of the car's oxygen sensors, so it admirable to get the decent code reading and diagnosis.

Audi A4 Check Engine Light Flashing

Although there are countless potential causes of an illuminated Check Engine Light, we know from years of providing Check Engine Light Diagnosis Service that there are several common causes including something as simple as a loose gas cap. Other common reasons for a Check Engine Light are faulty head gasket, faulty emissions control part, a malfunction with the fuel injection system, dirty mass airflow sensor, damaged oxygen sensor, or defective spark plugs to name a few. No matter what is the root cause of the Check Engine Light, we have the Audi Certified Technicians and the certified service protocol to isolate the root problem and repair it as needed to restore factory specifications. When this happens, the Check Engine Light turns off, and you can leave the service center knowing that your Audi issue was fixed.

Every Audi A4 was designed with a high-technology performance monitoring system with a computer, and a series of sensors positioned strategically throughout the vehicle on its crucial systems. The sensors are continually detecting conditions while sending data to the electronic control unit. If the electronic control unit detects that the data is out of factory specifications, the Check Engine Light illuminates telling you that there is a problem. However, that is the limitation of the Check Engine Light – it won’t tell you what exactly is wrong nor what to do about it. That’s where we come in; Audi North Atlanta provides a Check Engine Light Diagnosis Service that isolates the core problem and gives you a recommendation on what to do next from a Highly Qualified Service professional.

How many miles can you drive with the check engine light?

The safest bet is to decipher the code and then plan your strategy accordingly. If you check engine light is twinkling, we pick that you pull over and contact Audi North Atlanta to aid pick if your vehicle is safe to drive in or if we pick a tow truck. Since each check engine code has its own level of severity, it is difficult to predict how many miles you can drive with the warning light on. It could be anything from a bad sensor to plug wires needing to be replaced.

Will the check engine light reset itself?

The check engine light on your Audi A4 will usually shut itself off if the issue or code that caused it to turn on is fixed. For example, if the cause of your check engine light coming on was a loose gas cap, if it's tightened, the light will turn itself off. Likewise, if your catalytic converter is going functional, and you did a lot of stop-and-go driving, that may have turned on the check engine light due to the high usage of the converter. In most cases, your Audi A4 light will go off after about 20-40 miles. If you drive over that amount and the light is still on, you will need to bring it in to Audi North Atlanta so the light and code can be double-checked and reset.

Is it safe to drive your Audi A4 with the check engine light on?

If the check engine light is flashing, this means that there is a exacting issue and it is recommended to service your Audi A4 abruptly. This question is not very natural because it all depends on the severity of the issue. If the cause is a minor issue, such as a loose gas cap, it should be safe to drive. This is frequently indicated by a steady glow of the check engine light. If you notice a difference in the performance of the vehicle, it could be an indication of a more rigorous problem. Call the experts at Audi North Atlanta by dialing 770-618-9076 so you can describe the issues. Or lower down your speed and bring your Audi to our certified mechanics as soon as attainable.

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