Fickle check engine light

My CR-V’s check engine light went on & the next AM I went to the dealership for diagnostic testing. They performed computer diagnostics & a multi-point inspection (which was most recently done and passed 4 months ago). I was told I needed an O2 sensor replaced to the tune of over $400, in addition to a few other costly recommended repairs. Later that day the engine check light did not appear. Should I get a 2nd opinion & where? Auto Zone or Pep Boys okay?

CEL or not, the code could still be present. AutoZone and Pep Boys are not and should not be considered a diagnostic center.

The job of the parts house is to provide the customer a code only. If there is a code for an O2 sensor or a TPS switch then they should tell the car owner nothing more than that. Sometimes there is more to the code being provided than what meets the eye.

What were the other costly recommended repairs?

The O2 sensor could be bad, but often getting a O2 sensor-related code is just a symptom of something else going on. Depending on what code you’re getting, condemning the sensor based on just an error code is like thinking: “wow, I’m really burning up, I must have a fever” without realizing you have 2 sweaters on and are sitting in the sun.

Could you please post back the exact code that’s being read?

How old is the car, how many miles?

True, the sensor can be out of range or the heater circuit can be bad. 2 different issues. Changing a rear sensor takes 1/2 hr with coffee break. Front manifold sensors can be much harder to reach. What is labor/parts breakdown on job?

The Check Engine light will come on if for example the O2 sensors cross counts slow down. Then if the cross counts resume to normal the Check Engine light will turn off.

This is called a lazy O2 sensor.

Tester

2007 with 108,000 miles

Without knowing the code number, hard to make a recommendation. But if the dealership says the next step is a new O2 sensor, they probably know what they are talking about. Like mentioned above, O2 sensor codes often don’t exactly pinpoint the cause, but replacing the sensor might be the most economical first step. Be aware there may be other steps before the problem is totally corrected.

I guess what I’d do in this situation, since the light is now off, is to wait on it a bit. Maybe the light wont turn back on again. And – this is unlikely to be the cause but is easy to do so worth the time probably – check your gas cap to make sure it is sealing ok, and correctly tightened.

Edit: If you decide to replace the sensor, any good inde shop that specializes in this make could do it for you, and you’d likely get a better job. Dealerships are geared for dealing with warranty work on newer cars.