1999 Chevy Suburban Oxygen sensor and evaporative purge sol

  • V8
  • 2WD
  • 156,000 MILES
Can you tell me where both of these are located and how to replace them? Both are supposedly bad and are causing to fail the inspection test. Thank you.
Do you
have the same problem?
Saturday, August 29th, 2009 AT 1:20 PM

2 Replies

Which oxygen sensor? There are 4 Heated o2 sensors on the exhaust pipe. Bank 1 sensor 1 left side just below exh manifold to pipe connection, bank 2 sensor 1 r side same location, Bank 2 sensor 2 r side just aft of catalytic converter, bank 1 sensor 2 same location on left side.
The Heated Oxygen Sensors are mounted in the exhaust system where they can monitor the oxygen content of the exhaust gas stream. The oxygen present in the exhaust gas reacts with the sensor to produce a voltage output. This voltage should constantly fluctuate from approximately 100 mV (high oxygen content - lean mixture) to 900 mV (low oxygen content - rich mixture). The heated oxygen sensor voltage can be monitored with a scan tool. By monitoring the voltage output of the oxygen sensor, the PCM calculates what fuel mixture command to give to the injectors (lean mixture - low HO2S voltage = rich command, rich mixture - high HO2S voltage = lean command).
When the VCM detects a malfunction in the HO2S heater circuits, the following DTCs will set:
" DTC P0135 Bank 1 Sensor 1 heater.
" DTC P0155 Bank 2 Sensor 1 heater.
" DTC P0141 Bank 1 Sensor 2 heater.
" DTC P0161 Bank 2 Sensor 2 heater.
When the VCM detects no HO2S activity, the VCM will set the following DTCs:
" DTC P0134 Bank 1 Sensor 1.
" DTC P0154 Bank 2 Sensor 1.
" DTC P0140 Bank 1 Sensor 2.
" DTC P0160 Bank 2 Sensor 2.
When the VCM detects an HO2S signal circuit that is high, the VCM will set the following DTCs:
DTC P0132 Bank 1 Sensor 1.
" DTC P0152 Bank 2 Sensor 1.
" DTC P0138 Bank 1 Sensor 2.
" DTC P0158 Bank 2 Sensor 2.
When the VCM detects an HO2S signal circuit that is low, the VCM will set the following DTCs:
" DTC P0131 Bank 1 Sensor 1.
" DTC P0151 Bank 2 Sensor 1.
" DTC P0137 Bank 1 Sensor 2.
" DTC P0157 Bank 2 Sensor 2.


CAUTION : The Heated Oxygen Sensor (HO2S) and the Oxygen Sensor use a permanently attached pigtail and connector. Do not remove this pigtail from the Heated Oxygen Sensor. Damage or the removal of the pigtail or the connector could affect the proper operation of the sensor.

CAUTION : Take care when handling the HO2S. Keep the in-line electrical connector and the louvered end free of grease, dirt, or other contaminants. Also avoid using cleaning solvents of any type. Do not drop or roughly handle the HO2S.

CAUTION : If the heated oxygen sensor pigtail wiring, connector or terminal is damaged, the entire oxygen sensor assembly must be replaced. Do Not attempt to repair the wiring, connector or terminals. In order for the sensor to function properly, it must have provided to it a clean air reference.

CAUTION : This clean air reference is obtained by way of the oxygen sensor signal and heater wires. Any attempt to repair the wires, connectors, or terminals could result in the obstruction of the air reference and degraded sensor performance. The following guidelines should be used when servicing the heated oxygen sensor:

" Do Not apply contact cleaner or other materials to the sensor or vehicle harness connectors. These materials may get into the sensor causing poor performance.
" The sensor pigtail and harness wires must not be damaged in such a way that the wires inside are exposed. This could provide a path for foreign materials to enter the sensor and cause performance problems,
" Neither the sensor or vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks, etc., could block the reference air path through the lead wire.
" Do Not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize the ground wired sensor may rely on this ground as the only ground contact to the sensor. Removal of the ground wire will cause poor engine performance.
" To prevent damage due to water intrusion. be sure that the peripheral seal remains intact on the vehicle harness connector. The engine harness may be repaired using Packard's Crimp and Splice Seals Terminal Repair Kit. Under no circumstances should repairs be soldered since this could result in the air reference being obstructed.
CAUTION : The Heated Oxygen Sensor (HO2S) may be difficult to remove when the engine temperature is below 48 C (120 F). Excessive force may damage the threads in the exhaust manifold or the exhaust pipe.


1.Disconnect the negative battery cable.
2.Remove the electrical connector by releasing the locking tab.
3.Carefully back out the heated oxygen sensor.

NOTE : A special anti-seize compound is used on the Heated Oxygen Sensor (HO2S) threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn away, but the glass beads remain, making the sensor easier to remove. New, or service replacement sensors already have the compound applied to the threads. If the sensor is removed from an engine and if for any reason it is to be reinstalled, the threads must have anti-seize compound applied before the reinstallation.

1.Coat the threads of the oxygen sensor with anti-seize compound GM P/N 5613695 or the equivalent if necessary.
2.Install the sensor. Tighten
" Tighten the sensor to 41 Nm (30 lb. ft.) .
3.Install the electrical connector.
4.Connect the negative battery cable.
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Thursday, September 3rd, 2009 AT 9:45 AM
Loaction on r side of intake manifold looking forward, just forward of igniton coil area. Look for black plastic hose connecting to it. Two vertical mounting bolts. I believe 10mm. One electrical plug on top. Disconect plug, remove nut from mounting stud, disconnect hose, lift out of intake manifold.


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Thursday, September 3rd, 2009 AT 9:59 AM

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