Skip the auto shop - Our mechanics make house calls

Q: Why does the check engine light keep coming back on?

asked by on

I have 97,000 miles on my 2006 GMC Sierra, and recently I have had to get the Check Engine light reset more than once. It first came on when some sensor went bad, but when it came back on not too long later, the mechanic looked at it and didn’t find anything. Is this going to be an ongoing problem? Is it possible that something broke when the sensor was replaced? This is my work truck so I plan on getting some more life out of it yet.

A: The check engine light comes on and stays o...

The check engine light comes on and stays on if the onboard computer sees a problem that could cause an increase in emissions or a problem with its systems. After looking at most of the possible codes or issues that could cause the check engine light to come on. The most common problem your vehicle is having is an evaporative system problem since you say a technician could not find any problems. The fuel tank evaporative system vent solenoid could be the failure because they are prone to getting dirt and debris in the solenoid filter causing them to not vent the tank properly. The valve will operate electrically.

My recommendation would be to have your computer system checked for codes relating to the evaporative fuel tank system by a qualified mechanic. A certified mechanic with YourMechanic can inspect and diagnose the fuel tank system at your home or office. The fix recommendation would be to replace the evaporative vent solenoid and the fuel tank cap.

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・Save up to 30%

Get a quote

What others are asking

Q: Check engine light, ABS light on

Hello, thanks for writing in. If the check engine light is coming on and going off then usually it is not too serious. Most of the time this is caused by a sensor that is not reading quite right. The...

Q: After filling my car up with gas, it has a labored start

I would first retrieve the trouble codes, to see if that can shed some light on what the issue may be. If this problem occurred only after you filled up, then it may possibly be a problem with the type...

Q: the car has suffocation feeling when accelerator is pressed and does not speed constantly

This sounds like a low fuel pressure problem, or an air filter and mass airflow (MAF) sensor problem. Check the fuel pressure and replace the fuel filter first to see if it helps. Next, have the system computer scanned...

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...
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...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.