What caused my check engine light to turn on?


An illuminated check engine light doesn't automatically indicate that your engine is on the cusp of disaster. But you'll still want to visit the shop so computerized diagnostics can be done. This way, any emerging issues can hopefully be taken care of before they cause extensive problems and become very expensive to fix. Here are seven reasons the check engine light comes on.

Failing Catalytic Converter

To ensure that your vehicle is minimally polluting, you need a healthy catalytic converter. Symptoms of catalytic converter trouble include darkened exhaust smoke and poor acceleration. With a bad catalytic converter, you may also notice a smell like rotten eggs.

Bad Oxygen Sensor

Oxygen sensors do the important task of monitoring how much unburned oxygen is in the exhaust system. A faulty oxygen sensor may not only trigger the check engine light, it could also lead to catalytic converter problems.

Faulty Mass Air Flow Sensor

MAF sensors keep tabs on how much air is coming in and calculate the amount of fuel that should be injected with it. A failing MAF sensor could cause hesitations during acceleration.

Battery/Charging System Issue

A bad battery can cause low voltage at the computer, which could consequently cause the check engine light to turn on.

Faulty Spark Plugs

Failing spark plugs can cause performance and fuel-efficiency to worsen. Vehicles manufactured after 2000 can regularly go 100,000 miles before needing new plugs, while older cars tend to need their plugs replaced more often.

Poorly-Fitting Gas Cap

Even though it might sound strange, a loose or missing gas sometimes triggers the check engine light---and could also allow gas to evaporate before you get the chance to run on it.

Bad Ignition Coil

To reliably create the spark your engine needs to come roaring to life, you need healthy ignition coils. An ignition coil issue could cause misfiring.

If you need auto repair, be sure to visit a reputable mechanic. For check engine light diagnostics and repair in Covina, Pomona, Baldwin Park, and San Dimas, CA, contact the experts at Hye-Tech Auto at (626) 332-5452. Feel free to give Hye-Tech Auto a call today to make an appointment for any of your vehicle's repair or maintenance needs!


Hye Tech Auto Blog
Posted: May 3, 2021

Written & Published By MORBiZ


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