Seeing your vehicle's check engine light illuminate can be highly concerning. This warning light is part of your vehicle's onboard diagnostic system, which monitors engine performance, emissions, and related components. While some triggers involve relatively minor issues, others can indicate problems that require prompt professional attention. Ignoring the warning may allow an underlying issue to worsen and potentially lead to additional damage. At Mendo Motorz & Transmissions, we provide expert check engine light diagnostics and repair in the greater San Antonio area. Here are four common reasons your check engine light may turn on.

Faulty Oxygen Sensor

Oxygen sensors measure the amount of oxygen in the exhaust gases, helping the engine computer regulate the air-fuel mixture. When the sensor begins to fail, the engine may use fuel less efficiently or produce higher emissions. Replacing a faulty sensor when necessary can help restore proper engine management and prevent related performance issues.

Worn or Failing Spark Plugs

Spark plugs ignite the air-fuel mixture inside your engine's cylinders. When they become worn or damaged, combustion may become inconsistent, causing engine misfires. A misfire can trigger the check engine light and may produce rough idling, hesitation, reduced power, or increased fuel consumption. Ignoring persistent misfires can potentially damage the catalytic converter. Your mechanic can determine whether the spark plugs, ignition coils, or another component is responsible.

Malfunctioning Mass Airflow Sensor

The mass airflow sensor measures how much air enters the engine so the computer can deliver an appropriate amount of fuel. If the sensor becomes contaminated or fails, the engine may receive inaccurate airflow readings. This can lead to rough idling, hesitation during acceleration, poor fuel-economy, or difficulty starting. Professional diagnostics can determine whether the sensor needs cleaning, replacement, or if you need further testing of the air intake system.

Failing Catalytic Converter

The catalytic converter reduces harmful emissions before exhaust gases leave your vehicle. If it becomes damaged, clogged, or less effective, the check engine light may illuminate. Other symptoms can include reduced engine power, sulfurish odors, and poor fuel-efficiency. Problems elsewhere, such as persistent engine misfires, can contribute to catalytic converter damage, so identifying the underlying cause is essential.

Check Engine Light Diagnostics and Repair in San Antonio, TX

For expert auto repair in San Antonio and the surrounding area, contact Mendo Motorz & Transmissions at 726-233-2226. Feel free to give us a call to schedule an appointment for car care in greater San Antonio!