Why is my check engine light on? Here are 5 common triggers

July 27, 2024

When the check engine light illuminates, it's a sign from your car that something isn't right. While the issue could be minor, it's always best to investigate promptly to avoid more serious problems. At American Five Star Auto Repair & Transmission, we provide expert check engine light diagnostics and repair in the greater Tempe area. Here’s a look at five common reasons the check engine light illuminates.

Oxygen Sensor Failure

The oxygen sensor monitors the level of unburned oxygen in your vehicle's exhaust system and sends this information to the engine control unit (ECU). This helps the engine run efficiently and reduce emissions. A faulty oxygen sensor can lead to decreased fuel-economy, increased emissions, and potential problems with the catalytic converter.

Catalytic Converter Issues

The catalytic converter is an important component of your vehicle’s exhaust system. It helps convert harmful pollutants into less harmful emissions before they exit the exhaust system. If the catalytic converter fails, your car will not only emit more pollutants, but you can also experience reduced performance and fuel-economy. 

Mass Airflow Sensor Problems

The mass airflow (MAF) sensor measures the amount of air entering the engine and helps the ECU determine the proper amount of fuel to inject. If the MAF sensor is faulty, it can result in incorrect air-fuel mixtures, leading to poor engine performance.

Loose or Faulty Gas Cap

One of the simplest reasons for a check engine light to illuminate is a loose or faulty gas cap. The gas cap seals the fuel system. If it’s loose or faulty, fuel may evaporate before you get the chance to run on it.

Spark Plug or Ignition Coil Issues

Spark plugs and ignition coils are essential for igniting the air-fuel mixture in your engine’s cylinders. Worn-out spark plugs or faulty ignition coils can cause misfires, leading to rough engine performance. Regular replacement of spark plugs and ignition coils can help keep your engine running smoothly.

Check Engine Light Repair in Tempe, AZ

When you need auto repair in Tempe and the surrounding area, contact American Five Star Auto Repair & Transmission at (480) 966-8181. At our local auto shop, we can expertly address your vehicle’s repair and maintenance needs. Feel free to give us a call today to make an appointment!

Why Do Car Batteries Die Faster in Arizona? | American Five Star Auto Repair & Transmission
September 26, 2025
If you live in Arizona, you’ve probably noticed that car batteries don’t seem to last as long as they do in other parts of the country. While most drivers elsewhere can expect three to five years from a battery, it’s common for Arizona batteries to give out in as little as two years. The intense desert heat plays a significant role, but several other factors also contribute. Knowing why this happens can help you take better care of your battery and avoid unexpected breakdowns. How Heat Affects Car Batteries Most drivers think cold weather is what drains a car battery, but extreme heat can actually be far more damaging. Inside your battery, chemical reactions produce the energy needed to start your car and power electrical systems. High temperatures speed up those reactions, which sounds like a good thing at first. The downside is that the heat also causes the battery’s internal components to wear out faster. Excessive heat evaporates battery fluid, which reduces its ability to hold a charge. It can also damage the plates inside the battery, making it harder for the battery to deliver power when you need it. Even though your car might start just fine for a while, the battery’s overall lifespan is being shortened every time it’s exposed to extreme heat. Under-the-Hood Temperatures Make Things Worse The Arizona sun is intense, but the heat doesn’t stop there. Under your hood, temperatures can climb well above 200 degrees, especially during summer driving. These conditions place additional stress on the battery and other components around it. If you’ve ever opened your hood after a long drive in the heat, you’ve experienced just how extreme these temperatures can get. Drivers who make frequent short trips are especially vulnerable. Every time the engine heats up and cools back down, the battery endures repeated thermal cycles, which accelerates internal wear. Heavy Electrical Demand Modern vehicles rely on far more electronics than older models. Between air conditioning systems running at full blast, infotainment units, power-hungry sensors, and driver-assist features, today’s batteries have a lot more work to do. In Arizona, where air conditioning often runs nonstop for months, the demand on the battery is even greater. If your alternator or charging system isn’t keeping up, the battery can’t fully recharge between trips. Over time, this constant strain shortens its lifespan, especially in the intense desert heat. The Role of Driving Habits Short trips and stop-and-go driving are common in city areas and contribute to battery wear. When you only drive a few miles at a time, the alternator doesn’t have enough time to fully recharge the battery. Combine that with the heat, and you have a recipe for frequent battery replacements. Longer drives at steady speeds allow the alternator to restore more energy to the battery. If most of your driving is around town, consider taking your car for a longer drive every so often to give the charging system a chance to catch up. How to Extend Your Battery’s Life While you can’t control Arizona’s climate, you can take steps to protect your battery and get as much life out of it as possible: Park in the shade or a garage whenever you can to reduce exposure to direct sunlight. Inspect and clean battery terminals regularly to prevent corrosion that interferes with charging. Check fluid levels if you have a serviceable battery, since heat accelerates evaporation. Test your battery often, especially before summer, to catch early signs of weakness. Have the charging system inspected during routine maintenance to ensure it’s keeping up with demand. These simple habits won’t make your battery immune to Arizona’s climate, but they can give you more time before a replacement is necessary. Signs Your Battery Is Failing Slow or hesitant engine starts. Flickering dashboard lights or dim headlights. Frequent need to jump-start the car. Warning lights related to the charging system. If you notice these symptoms, it’s best to have the battery tested as soon as possible. Waiting until it fails completely can leave you stranded, especially in extreme heat when roadside assistance may take longer to arrive. Keep Your Car Ready for Arizona Roads with American Five Star Auto Repair & Transmission At American Five Star Auto Repair & Transmission , we understand how Arizona’s heat affects your vehicle. Our technicians can test your battery, inspect the charging system, and help you stay ahead of problems before they cause a breakdown. Whether you need a quick checkup or a full battery replacement, we’ll make sure your car is ready to handle the desert climate. Schedule an appointment with American Five Star Auto Repair & Transmission today and drive with confidence knowing your battery and charging system are in top condition.
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