Hi everyone

I'm back after a long time ...
Please , I need help . I bought lastly a buick lesabre (2001 limited) . the last one I solded .

The "service engie soon" light was ON .
the codes that my scanner read : P0300 , P0137 , P0128 .
I reset the codes . after 40 Km the light shows again , again I connect my scanner and only P0137 code appear .

I want to know the location of "Bank 1 Sensor 2 oxygen sensor" .
there any suggestion how can i fix the other errors if they appear again ?

Thanks

You only have two O2 sensors....one before the cat, and one after the cat......this refers to the one after the cat.......

Several scenarios for this....bad sensor.....harness to sensor.....exhaust leak near sensor......

P0300....is associated with a misfire, usually secondary ignition(plugs, wires, coils, etc.)

P0128 is usually a bad thermostat, or temp sensor.....more often the thermostat....

thank you
I'll check it soon

Hi
I solved the P0300 and P0128 codes .
but the P0137 not yet , actully , I clean the sensor and clear the code . the code not return 3 weeks . today , the light "service engine soon" start again .
but now I have 2 faults , P0137 and P0141 .
what could be the reason for that ?
I have to replace the O2 sensor ?

thanks

Both codes refer to the O2 sensor after the cat...

P0141 refers to the time it takes for an O2 sensor to respond.....the new O2 sensors incorporate a heater element....this helps the O2 sensor to get up to operating temp faster......without the element, it takes longer for the O2 sensor to respond....the PCM "times" how long it takes for this sensor to respond.....if it takes longer than what is programmed into the PCM, this sets a code....several things can cause this to happen, one is a harness problem and two, is the heater element in the O2 sensor......If the harness is cut(open), or if it is grounded(it'* shorted and will blow the fuse to the heater element)....so a visual inspection should be given to the harness, if ok, a test light should be attached to the heating element circuit(the half of the connector going back to the PCM, not the half of the connector going to the O2 sensor) and the key turned to on....if the test light lights, the fuse is ok, and the circuit is ok, and the problem is the element, and the O2 sensor should be replaced.....

P0137 sets when the PCM detects that the downstream O2 sensor is detecting a constant low lean condition....what the PCM will do, is briefly enrichen the mixture, looking for a change in the reading for the rear sensor...if it doesn't see it, it will set the code.....several factors can cause this....one, an exhaust leak near/before the second O2 sensor....two, bad connection in the harness, or harness problems......three, a contaminated/fouled sensor.....fourth, a bad sensor.....

In your case I would tackle P0141 first....If there is no open or shorted circuit, and the fuse is ok, then the problem is the element, so replace the O2 sensor.....this may be a two-for........replacing the O2 sensor for one code may take care of the other code....that'* what I would do....