Pontiac P0142 O2 Sensor Circuit Malfunction Bank 1 Sensor 3

Description

OBD-II Trouble Code Description for P0142 Pontiac

O2 Sensor Circuit

What does this mean?

OBD2 Code P0142 Pontiac definition:
The oxygen sensors are critical to the engine running properly. It basically informs the PCM (Powertrain Control Module) of oxygen content of the exhaust. The PCM then uses this information to regulate fuel injector pulse. Inaccurate or faulty O2 sensors can cause the PCM to add or take away fuel based on the faulty O2 sensor voltage which can cause a host of problems. A P0142 Pontiac code definition:the Bank 1,3 O2 sensor or the 3rd downstream (post-cat) O2 sensor on Bank 1. It is a four wire sensor. The PCM supplies a ground circuit and a reference voltage circuit of about 0.5 volts. Also for the O2 sensor heater element there is a battery voltage supply wire and another ground circuit for that. The O2 sensor heater allows the O2 sensor to warm up faster, thus achieving closed loop in less time than it would normally take for the exhaust to warm the sensor up to operating temperature. The O2 sensor varies the supplied reference voltage based on oxygen content in the exhaust. It is capable of varying from about 0.1 to 0.9 volts, 0.1v indicating lean exhaust and 0.9v indicating rich exhaust. This P0142 Pontiac code indicates that the Bank 1,3 O2 sensor is stuck low for too long or isn’t active at all.

Symptoms

Possible sumptoms of OBD code P0142 Pontiac
Often post-cat O2 sensor problems present few symptoms since they are inputs to the PCM to monitor catalytic converter quality and don’t directly control fuel. sometimes no symptoms are noticeable. However the following may be possible on some vehicles: MIL (Malfunction Indicator Lamp) illumination Decrease in MPG Increase in tailpipe emissions

Causes

Possible causes of OBD code P0142 Pontiac
Potential causes of a P0142 Pontiac code include: Bad O2 sensor Signal shorted to voltage Wiring problems due to contact with exhaust components Holes in exhaust near O2 sensor

Possible Solutions

If you have access to a scan tool, check the signal voltage for the Bank 1,3 oxygen sensor with the engine at normal operating temperature. Is it stuck low currently? If so, increase RPM for a few seconds and see if it affects the reading. If it begins working with increased RPM, check for holes in the exhaust near the O2 sensor that may cause a false lean. If the exhaust pipe is intact, the sensor is sluggish, replace it. If the Bank 1,3 O2 sensor voltage reading remains low with increased RPM, unplug it and then observe the reading. It should have increased to about 0.5 volts or thereabouts. If it did, check for water intrusion or other connector problems. If none are found, replace the shorted O2 sensor. If the voltage reading is still stuck low after unplugging the sensor, then suspect a wiring problem. Using a voltmeter, with the O2 sensor unplugged, check for voltage on the signal circuit at the O2 sensor connector (PCM side). It can vary with model, but should be about 0.5 volts and not above 1 volt. If the voltage reading is too high, repair short to voltage on signal circuit. If the signal voltage checks out, suspect the PCM.

Related Codes

P0141 Pontiac P0140 Pontiac P0143 Pontiac P0144 Pontiac


The OBD2 Code Information Be Applicable For Pontiac:

2010 Pontiac G8,2009 Pontiac G8,2009 Pontiac G6 ,2009 Pontiac G3,2008 Pontiac G8,2007 Pontiac Solstice SD-290 Concept,2007 Pontiac Solstice GXP,2007 Pontiac G6 GXP Show Car,2006 Pontiac Torrent,2006 Pontiac Solstice,2006 Pontiac Montana SV6,2006 Pontiac GTO,2006 Pontiac G6 GTP Coupe,2006 Pontiac G6 GTP Convertible,2005 Pontiac Vibe GT,2005 Pontiac Montana SV6,2005 Pontiac Grand Prix,2005 Pontiac Grand Am GT Coupe,2005 Pontiac GTO,2005 Pontiac G6 GT,2004 Pontiac Grand Prix GTP,2004 Pontiac Grand Am GXP,2004 Pontiac GTO 5.7,2004 Pontiac GTO,2004 Pontiac Bonneville GXP,2004 Pontiac Aztek Rally,2003 Pontiac Vibe GT,2003 Pontiac Vibe,2003 Pontiac Sunfire Coupe,2003 Pontiac Montana Thunder,2003 Pontiac Grand Prix,2003 Pontiac Grand Am SE Sedan,2003 Pontiac G6 Concept,2003 Pontiac Aztek,2002 Pontiac Sunfire GXP,2002 Pontiac Sunfire American Tuner,2002 Pontiac Solstice Concept,2002 Pontiac REV Concept,2002 Pontiac Grand Prix GXP,2002 Pontiac Grand Prix G-Force Concept,2002 Pontiac Firebird Trans Am Edition,2001 Pontiac Vibe GT,2001 Pontiac Vibe,2001 Pontiac Sunfire HO,2001 Pontiac Sunfire Accessorized,2001 Pontiac Montana,2001 Pontiac Grand Prix

 

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