What should I do when my check engine light comes on?


Vehicles have three kinds of lights: check engine, service required and maintenance required.

You should always pay attention to any light you see, but the color matters, and so does solid or flashing light. If you get a solid warning light that is yellow or amber, you can probably continue to drive safely. Red is more serious. A red light is generally associated with the engine’s temperature, the oil, the battery or open doors.

If you see a red light or a flashing yellow or amber light, stop the vehicle as soon as you can safely do so. Flashing lights are as serious as red lights. You could damage your vehicle if you continue to drive, so stop driving as soon as you can. A flashing check engine light may mean the engine is misfiring. The engine or catalytic converter (which are both expensive) could be damaged.

If a solid light comes on, pay attention to how the vehicle is driving. Do you notice anything unusual? You should probably stop driving. Does everything seem normal? Slow down, avoid sudden acceleration or gear shifts, and drive to a safe location. A yellow or amber check engine light probably means something is wrong in the powertrain or other related components.

Manufacturers have designed vehicles that will identify the nature of the problem by using codes. Bring your vehicle to your local Tunex after the check engine light comes on. Our mechanics will read the code for free and, with your consent, use it as a starting point for figuring out the extent of the problem.

The most common reasons for the check engine light to come on can be categorized:

  • The engine isn’t working correctly.
  • The transmission has a problem; that sometimes increases tailpipe emissions.
  • Part of the emissions equipment has failed.
  • There are problems with the electronic powertrain’s controls.
  • Air and fuel delivery are not working correctly.
  • The ignition system has a problem.

Utah and Idaho currently require emissions testing, although newer cars don’t have to be tested every year. Owners should know that emissions and engine function are closely related, and they should take that into account if they are thinking about waiting for repairs. Your vehicle may not pass an emissions test unless the engine is working correctly.

If you see any engine light come on, please bring your vehicle in to have us fix the problem for you.