Wondering what causes the Check Engine Light to Come On?

You may be driving smoothly along when all of a sudden you see the “Check Engine” light illuminate on your dashboard.  You start to worry about what causes the check engine light to come on.  This little light could be the first warning sign of an engine problem.  Unless your car doesn’t run at all, head to your auto repair shop as soon as you can for a diagnostic test.  Your mechanic will hook up a specialized computer to your vehicle to “read” what is going on under the hood.  Potential problems can be diagnosed and fixed while they are small problems, and before they turn into major engine repair.  

There are few problems that can cause the check engine light to come on:

1. Faulty Gas Cap – When the gas cap is loose or cracked, fuel vapors leak out and can throw the whole fuel system off.
2. Faulty Oxygen Sensor – If the oxygen sensor fails, it’s not providing the right data to the car’s computer to monitor the unburned oxygen from the exhaust and how much fuel should be burned. 
3. Failing Catalytic Convertor – If the catalytic convertor fails, it can’t do its job of reducing exhaust gases. It converts carbon monoxide and other harmful materials into harmless emissions.
4. Faulty Mass Airflow Sensor – The mass airflow sensor tells the car's computer to add the proper amount of fuel based on the air coming through to the engine.  Most mass airflow sensors fail because of an improperly installed or it becomes clogged.
5. Bad Spark Plugs and Wires – The spark plug seals the combustion chamber and provides a gap for a spark to jump across and initiates combustion in your engine.  You will start to notice misfiring when spark plugs go bad.

Any of the issues listed above can result in reduced fuel efficiency, an increase in toxic fumes from your exhaust, loss of power, rough idling, or not running at all.   If you want to prevent major and expensive engine repair, as well as keep your vehicle a reliable means of transportation, don’t neglect regular engine service.  

If you need to know more about what causes the check engine light to come on, call our ASE Certified technicians at Auto & Fleet Mechanic for more information about engine repair and to make an appointment. Our auto repair shop proudly serves residents in Modesto, CA, and the surrounding area.

Wondering, “Can You Drive a Car with the Engine Light on?”

If the check engine light comes on while you’re driving, don’t panic!  Pay attention and see if the car is driving any differently than usual.  You may be wondering, “Can you drive a car with the engine light on?”  Whether or not it’s safe to keep driving with the check engine light on depends on vehicle performance and the root cause of its illumination.  Just be sure to have your car checked as soon as possible after the light turns on.  Don’t neglect needed engine repair!

If nothing appears out of the ordinary, you can continue driving the car. The cause could be anything from a defective oxygen sensor to a bad MAF sensor. It could also mean your catalytic converter has failed and quit working. 

Here are three steps to help you determine whether it’s safe to continue driving or if you want to stop instantly:

1. What else is wrong?  -  In addition to the check engine light, your dashboard may also indicate low oil pressure or overheating problems. If these lights come on, pull over and shut off the engine as soon as you can. Several cars may have a red check engine light to alert you to stop right away, while a yellow light stands for analysis. 
2. Take it easy! -  If performance issues accompany the check engine light, lower your speed and take it easy on the engine. Avoid speed surges and erratic shifting. If you’re towing a trailer or carrying heavy equipment, try to unload as soon as you can to prevent a potentially expensive engine repair. 
3. Tighten the cap! - If the light comes on after refueling, inspect that the gas cap is tight.  The sensor is detecting a leak in the evaporative emissions system.  It may take some restarts of the engine to reset the light.  

The check engine light is tied into your car’s onboard diagnostics system, and it’s designed to light up whenever something goes wrong with any of the components and sensors. Issues in the electronic control system are stored in a “trouble code” to identify the source of the problem.  With the use of a diagnostic computer, your mechanic can pinpoint the issue and take care of any compulsory adjustments or repairs. 

Are you wondering can you drive a car with the engine light on?  Call our ASE Certified technicians at Auto & Fleet Mechanic for more information about engine repair and to make an appointment. Our auto repair shop proudly serves residents in Modesto, CA, and the surrounding area.