Skip the auto shop - Our mechanics make house calls

Q: Does the O2 sensor make the engine check light appear?

asked by on

Some times when I turn the car on the rpms are going up and down, and have to turn it off and back on to function right

My car has 144000 miles.
My car has an automatic transmission.

A: Hi, thanks for writing in. To answer your q...

Hi, thanks for writing in. To answer your question simply-- YES, it is very common for the check engine light to illuminate when the O2 or air/fuel ratio sensors are acting up. When the sensor detects an issue inside the fuel manifold, or if the sensors are damaged it will trigger an OBD-II error code to be stored in the ECM. This in turn illuminates the check engine light. The rising RPMss may be caused by one of these components, but the only way to determine which one is to complete a diagnostic scan to pull those error codes and determine the culprit. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to perform the scan for you.

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: Problems with shifter

Hello, I am assuming that your shift is hard to get out of park and maybe past reverse. In August of 2010, Dodge put out a campaign for this issue. A campaign is not a recall, but it is similar....

Q: Engine is sputtering

Hi, the Check Engine Light flashing commonly indicates a misfire in the engine. The most common cause of an engine misfire on this particular car would be the ignition coil. The ignition coil can generate an output voltage on the...

Q: Driver's side mirror moves straight up on its own

Hello there, the mirror issue you have described can be problematic for everyday driving. There a few causes for this fault. Most common would be the mirror control computer, mirror control switch, or the mirror actuators. A qualified technician, such...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
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...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...