What problems cause check engine light?

What problems cause check engine light?

Spark Plugs Finally, worn spark plugs or plug wires will result in a check engine warning. Just about anything wrong with your vehicle’s ignition system will likely cause your check engine light to come on.

Why does my car show check engine light?

The check engine light — more formally known as the malfunction indicator lamp — is a signal from the car’s engine computer that something is wrong. If the light begins flashing, however, it indicates a more serious problem, such as a misfire that can quickly overheat the catalytic converter.

What do I check when the check engine light comes on?

What to Do About the Check Engine Light

1. Look for a serious problem that requires immediate attention. Check your dashboard gauges and lights for indications of low oil pressure or overheating.
2. Try tightening your gas cap.
3. Reduce speed and load.
4. Use built-in diagnostic services, if available.

How do you pass a smog trick?

6 Proven Methods for Passing an Emissions (Smog) Test:

1. Test a very warm car on a cool day.
2. Use a specialized fuel additive.
3. Inflate tires to the proper (high) level.
4. Perform an oil change.
5. Turn off your “Check Engine” light (if needed).
6. Find a shop that offers a free retest.

How do you reset check engine light after tightening gas cap?

How to Reset the Warning Light Gas Cap That Is Loose or Missing

1. Turn off your vehicle’s engine.
2. Step to the gas cap door.
3. Replace the gas cap.
4. Close the gas cap door.
5. Use an OBD-II code scanner if the warning light does not disappear.
6. Continue driving the vehicle.

How can I tell if my gas cap is bad?

Symptoms of a Bad or Failing Gas Cap

1. Cap does not tighten properly. One of the most common symptoms of an issue with the gas cap is a cap that does not tighten properly.
2. Fuel smell from the vehicle. Another symptom of a possible issue with the fuel cap is a fuel smell from the vehicle.
3. Check Engine Light comes on.