Skip the auto shop - Our mechanics make house calls

Q: The check engine light often comes on and goes off after a well.

asked by on

The check engine light often comes on and goes off after a while. Any time I notice it whiles driving, I park and close the fuel tank well but the light doesn't go off. Sometimes I restart the car but it still won't go off. It goes off on it own and comes back after some time. What could be the cause?

My car has 137531 miles.
My car has an automatic transmission.

When the Check Engine Light comes on, that means that Trouble Codes, likely identifying the causes of the issue you are having, have been stored in your car’s computer. The fastest way to resolve this is to have a Check Engine Light Diagnostic performed to obtain those Codes and start to track down the possibilities. Such a Diagnostic can be done by a certified Mechanic from YourMechanic on a mobile basis. The Codes are downloadable using a scanner and they should indicate at least the general area of the fault. A possibility is that some engine management system has a poor electrical connection or other wiring problem that is evidencing itself only intermittently. But, there are other possible causes of intermittent illumination of the Check Engine Light such as failures in engine sensors, intermittent misfires, and faults with sticky or stuck valves such as in the EGR (exhaust gas recirculation) system or the EVAP system. The best thing to do is get a Check Engine Light Diagnostic and then it will be clearer as to what segment of the engine controls needs to be looked at in more detail.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Engine shudder while driving, burnt rubber smell

Hello. Most of the time, this is the first indication that the timing belt is failing. The timing belt needs to be checked to see if it is going bad. If the belt is fine, then you may have a...

Q: I have a CLS550 I was driving on the Interstate and Suddenly my car gave me a message saying pull over stop driving car too low wh

Hi there. This error message typically comes on when there is a leak in the air suspension of the Mercedes-Benz CLS-550. If you'd like to have one of our mobile mechanics come to your location and complete a suspension inspection,...

Q: Broken line

A copper line from the exhaust manifold to the engine bay sounds like an EGR pipe to me. If that's broken, the EGR won't be working as it should, and would just be injecting clean air as opposed to reusing...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...