Why the Service Engine Soon light turns on when...?

Question

I am waiting in a traffic light for more than 1 minute but later after moving the car it turns off,. That happens also when I keep 65 miles speed for a long period of time and after reducing speed it turns off
Other symptom, I feel a strong odor of combustion only when I am stopped in a traffic light or traffic jams

Answer 1

Take it somewhere and have the codes pulled and see what they are.

Answer 2

If there's an http://www.autozone.com auto store near you, get the error codes read out and you'll be able to diagnose the problem further. Read the check engine light tutorial below, and it will be worth your time:
http://www.samarins.com/diagnose/checkengine.html

Also, give the make, year, model, engine size of your car next time and that helps technicians troubleshoot your problem.

Any engine misfire condition that results in an overly rich air/fuel ratio might set an oxygen error code which is the most likely sensor turning your yellow check engine light on. Likewise, the gas rich exhaust burns up in your hot catalytic converter and you might notice an associated smell.

Answer 3

Sounds like low coolant level, and/or high engine temperatures.