P0141 code change 2 of 3 o2 sensors and code still comes bk is it the o2 after the cat???????????

standing in front of the vehicle looking at the engine bank 1 sensor 2 is the sensor after the cat converter on the bank on your left
bank one is the left cat ---bank 2 is the right cat. Sensor 1 is the one before the cat and sensor 2 is the one after the cat on either side

The P0141 code refers to your o2 sensor heater circuit. while many times replacement of the o2 sensor can solve this problem you possibly have a short or open in your o2 sensor heater circuit. Also was the proper o2 sensor changed p0141 is the bank 1 number 2 sensor. Bank 1 refers to the side of your engine where the #1 cylinder is located sensor 2 should be the second sensor on that side depending on how many sensors you vehicle has. hope this helps

The fault code P0135 means O2 Sensor Heater Circuit (Bank 1 Sensor 1)
The code P0141 means O2 Sensor Heater Circuit (Bank 1 Sensor 2)

Launch X431 Connector

P0135 bank 1 sensor 1 open or short in wires,bad connections,bad sensor ,or bad ecm. P0141 bank 1 sensor 2 same diag as P0135. P0420 cat below threshold open or short, or faulty Ho2s sensors.you may have several problems. start with sensors circuit if good change sensors if not trace to ecm if reading not right replace ecm if all good replace sensors clear codes retest drive two drive cycles for cat to clear tests. then with no dtcs present test fuel pressure , injectors,then ignition system ,timing valves ,map,maf sensors,throttle sensor,crank sensor cam sensor, compression.

P0141 is O2 Heater Circuit (Bank 1, Sensor 2) It will be the sensor AFTER the cat on the side that has #1 cylinder. On your car it's the PASSENGER side.

This will be an after the cat designation.

P0141-o2 sensor heater circuit malfunction [bank 1 sensor 2 ]this is the o2 sensor after the cat converter need to check the wiring[harness] and connections for frayed ,damaged or partial connection or o2 sensor failure and needs to be replaced

P1133 HO2S Insufficient Switching - Read Our Article On Oxygen Sensor Codes For Help With This Pontiac Trouble Code (check your oxygen sensor also called O2 sensor)

All the codes you have listed come back and refer to the oxygen sensor. I would say that it is your problem. you vehicle may have 2

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http://www.honda-tech.com/showthread.php?t=2385730 good luck!

SECONDARY HEATED O2 SENSOR HEATER CIRCUIT FAULT SENSOR 2.