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Watching Your Check Engine Light

August 18, 2024

Did you know that most of the cars driving around Joliet, Illinois, carry more computer power than the Apollo 121 Lunar Module that landed on the moon in 1969?

New cars sold in the Joliet area have as many as 12 networked computers and over five miles (eight kilometers) of wiring. In fact, for the last decade or so, auto computers have been controlling about 85 percent of your vehicle's functions.

Cars have sensors for manifold air temperature, coolant temperature, manifold air pressure, airflow, throttle position, vehicle speed and oxygen content. All of this electronic wizardry is pretty complicated. So how do Joliet drivers know when there is a problem?

It's simple; the Check Engine light comes on. The computer monitors all the sensors and uses that information to decide what to adjust such as the fuel mix, spark timing and idle speed. In addition, the computer monitors its own circuits. When it finds a fault, it turns on the Check Engine light and stores a trouble code in the computer.

It can be pretty disturbing for Joliet drivers when the Check Engine light comes on. We wonder just how urgent it is. Generally speaking, it is not critical like a temperature or oil pressure light. When you get one of those it means STOP NOW! When the Check Engine light shows up, you should come in to Tuffy Joliet (South Plainfield) in Joliet to find out what the matter is as soon as possible.

Since 1996, there has been a strong emissions control component to the Check Engine diagnostic. But if your Check Engine light flashes on and off, you know that it is more urgent and you need to get it checked immediately to prevent damage. You should slow down and avoid towing or heavy loads until you can get it checked out.

Your friendly and knowledgeable technicians at Tuffy Joliet (South Plainfield) have special diagnostic equipment that will retrieve the trouble code from the computer and help him determine what is wrong. From there, we can fix it and get you back on the road.

Stop by if you're Check Engine light is on.

Tuffy Joliet (South Plainfield)
2031 SR 59
Joliet, Illinois 60586
815-436-1829

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