Check Engine Light:
Why does it come on, what to do, and what happens if you ignore it?

You’re driving to work, taking the kids to a ballgame, or running a routine errand… and then you see it – the Check Engine Light turns on. Ugh. For many people, the sight of a Check Engine Light triggers visions of a costly repair bill and a sense of worry, since most folks don’t really know what it means.

The Check Engine Light turns on when your vehicle’s computer (which monitors your vehicle’s performance) finds a problem in the electronic control system that it can’t correct. There are hundreds of sensors in your car, any of which can send a signal to your car’s computer telling it that something isn’t quite right.

In your owner’s manual, there will be a section with recommendations on what to do if the Check Engine Light comes on for your car that will give you a better idea of what to expect.

A common question I hear is: how long can I wait to take my car in when that Check Engine light comes on?
My standard answer is:

• If there are no drivability problems then you can keep driving and bring it to your automotive service provider to get the computer scanned in the next couple of days.

• But, if the check engine light starts flashing or your vehicle is having drivability problems (stalling, hard to start, slow to accelerate, black smoke coming out the back, etc.) you should immediately pull off the road, turn off the engine & have the vehicle towed in for repairs.

• If you continue driving when the light is flashing or the vehicle is having drivability issues, you can do catastrophic damage which could require an expensive repair. The longer you drive, the more expensive it becomes.

If you do have your vehicle towed, be sure to take it to your dealer if you’re under warranty. Engine work done by a shop other than your dealer can void your warranty.

In short, don’t panic if the Check Engine Light comes on. The Check Engine Light is really your friend. The car’s computer is working hard monitoring your car’s engine and making adjustments so you can jump in your car and rush off to where ever you need to be without a thought to your car’s performance. So, if that light comes on to tell you there is a problem, don’t ignore it.

If your car is acting weird then print out this form, fill it out and take it to your auto repair center. This information will help them find out what is wrong with your vehicle quicker, which will save you money!

Contact Information

Name: ________________________________________________________________

Year: _________           Make: ______________             Model: _________________

License Plate number: __________    Current Mileage: ____________________

Phone number you can be reached at: __________________________________

Email address (if best way to reach you): _______________________________

Check as many symptoms as needed to describe what is going on

Describe as best you can:

Weird Noises: _______________________________________________________

Weird Smell: ________________________________________________________

Looks Weird: ________________________________________________________

Feels Weird: ________________________________________________________

Happening outside of the car

____  Driver’s Front        ____ Passenger Front       ____  In engine compartment

____ Driver’s Rear        ____ Passenger Rear        ____ under the vehicle

Happening inside of the car  (indicate which window, door or seat)

____  Front Dash         _____  Windshield        Window ___________________

Door __________________________         Seat _______________________

_____   Feel it in the brake pedal      _____  Feel it in the steering wheel

_____    In the cargo area      _____  In the trunk area

When do you notice it?

_____   All the time      _____ Only when first starting engine

_____  After the car is warmed up            _____ When engine is hot

After driving ______ miles                After driving ______ minutes

_____  On dirt roads                           _____  Going up hills

_____  In stop and go traffic             _____  On the highway

_____  When stopping (braking)    _____  After coming to a complete stop

_____  When accelerating                _____  When decelerating

_____  When turning right             _____  When turning left

_____  Whenever it feels like it (no rhyme or reason)

At ______ mph ¨  Any speed, doesn’t matter

_____  When the A/C is on             _____  When the defrost is on

_____  When the heat is on           _____  When the radio / tape / CD is on

On a 5 Speed Transmission

When in ________ gear                        When shifting from ___ gear to ___ gear

_____  When shifting in reverse

© Auto Craftsmen Ltd  *  326 State Street, Montpelier, VT 05602   *   (802) 223-2253