code p0137
 

DTC P0137 HO2S Circuit Low Voltage Sensor 2?

whats is it?
what does this mean?

It likely means that you need a new oxygen sensor, or that you have a leak that is causing a lean running condition.

* The heated oxygen sensor pigtail may be mispositioned and contacting the exhaust system.
* A condition which causes a lean exhaust can cause DTC P0137 to set. The system will go lean if pressure is too low. The PCM can compensate for some decrease. However, if fuel pressure is too low, a DTC P0137 may be set.
* Correct fuel injector operation.
* Check for the following vacuum leaks conditions:
* Any disconnected or damaged vacuum hoses, refer to Emission Hose Routing Diagram.
* An incorrectly installed or malfunctioning crankcase ventilation valve, refer to Crankcase Ventilation System Inspection. See: Emission Control Systems\Positive Crankcase Ventilation
* Any vacuum leaks at the throttle body, the EGR valve, and the intake manifold mounting surfaces
* An exhaust leak may cause outside air to be pulled into the exhaust gas stream past the HO2S, causing DTC P0137 to set. Check for exhaust leaks near the HO2S 2 sensor.
* Check the throttle body inlet screen for damage or objects that may alter the airflow sample through the MAF sensor. If a problem is found, correct as necessary.
* Disconnect the MAF sensor. If the lean condition is corrected with the MAF sensor disconnected, replace MAF sensor. Refer to MAF Sensor Replacement.
* Fuel contamination Water, even in small amounts, can be delivered to the fuel injectors. The water can cause a lean exhaust to be indicated. Excessive alcohol in the fuel can also cause this condition.

:stupid:
What he said. :D

Do you have any symptoms other than the CEL?

uh!!! let me print this...

No.. the CEL came on when I was driving back from N. Carolina.

it could also mean

It's time to pull the battery connections and look for any corrosion or bad connections. While a few of us have seen the other O2 sensor react to voltage variations (code P0171 Sensor bank 1) it's possible that sensor 2 is seeing the voltage drop.

As well..I'd be under the car looking to ensure nothing damaged a wire or disconnected the O2 in any way.

And to clarify....

O2 sensor #2 is the one after your catalytic converter, under the car. ;)

And O2 sensor #2 has no effect on any PCM issues or performance/efficiency. It is not used for, and cannot cause fueling issues.

It is for emissions only, as an indication that the catalytic converter is/isn't doing it's job.

Hi, first post here. I know this is a million year old thread but was doing a google search after my wifes 2003 Lesabre threw the P0137 code today. The car is low mileage and is just lovely to drive. Anyway, we were pulling our boat with the car up a hill trying to maintain 95km/hr, the muffler blew out the side. At the same time the check engine light came on. Found this thread and it makes sense, a sudden lean condition and the light comes on. Just wanted other GM owners to know if your muffler goes with the pedal down the CEL will come on.

6 year old thread, yes, please start your own with a link showing the old thread for informational purposes.

Are you talking about the catalytic converter blowing a hole out the side?

If its the muffler, there is no way this could cause a P0137.