MIL PO155, I Searched, I'm Confused!
03-19-10, 06:08 PM
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MIL PO155, I Searched, I'm Confused!
1998 GS300 89K Miles 
I have a Check Engine (MIL) light. Connected my OBD II and it reports two occurrences of PO155. My ScanTool.net software shows 0.0V, Sensor 3, Bank 1. But searching on the CL Forum doesn't seem to confirm this description for PO155 MIL. I am finding people talking about Bank 2 Sensor 1 for this code.
From the diagram on the CL DIY Sticky it seems I need to change the pre-cat O2 sensor on the header closest to the firewall.
Can someone please confirm before I spend $80 on an electrical part I can't return? Also, If anyone can confirm the Denso part number and best place to get one online I would really, really appreciate it.
I have a Check Engine (MIL) light. Connected my OBD II and it reports two occurrences of PO155. My ScanTool.net software shows 0.0V, Sensor 3, Bank 1. But searching on the CL Forum doesn't seem to confirm this description for PO155 MIL. I am finding people talking about Bank 2 Sensor 1 for this code.
From the diagram on the CL DIY Sticky it seems I need to change the pre-cat O2 sensor on the header closest to the firewall.
Can someone please confirm before I spend $80 on an electrical part I can't return? Also, If anyone can confirm the Denso part number and best place to get one online I would really, really appreciate it.
03-19-10, 06:48 PM
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1998 GS300 89K Miles
I have a Check Engine (MIL) light. Connected my OBD II and it reports two occurrences of PO155. My ScanTool.net software shows 0.0V, Sensor 3, Bank 1. But searching on the CL Forum doesn't seem to confirm this description for PO155 MIL. I am finding people talking about Bank 2 Sensor 1 for this code.
From the diagram on the CL DIY Sticky it seems I need to change the pre-cat O2 sensor on the header closest to the firewall.
Can someone please confirm before I spend $80 on an electrical part I can't return? Also, If anyone can confirm the Denso part number and best place to get one online I would really, really appreciate it.
I have a Check Engine (MIL) light. Connected my OBD II and it reports two occurrences of PO155. My ScanTool.net software shows 0.0V, Sensor 3, Bank 1. But searching on the CL Forum doesn't seem to confirm this description for PO155 MIL. I am finding people talking about Bank 2 Sensor 1 for this code.
From the diagram on the CL DIY Sticky it seems I need to change the pre-cat O2 sensor on the header closest to the firewall.
Can someone please confirm before I spend $80 on an electrical part I can't return? Also, If anyone can confirm the Denso part number and best place to get one online I would really, really appreciate it.
P0155 is a Heated Oxygen Sensor Heater Circuit (Bank 2 Sensor 1)
Bank 1 refers to the bank that includes cylinder # 1. Cylinders 1,2,3
Bank 2 refers to the bank that doesnt include cylinder # 1. Cylinders 4,5,6
Sensor 1 refers to the sensor before the cat.
Sensor 2 refers to the sensor after the cat.
The OEM part number is: 8946530440
03-23-10, 03:46 PM
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Replaced O2 sensor Bank 2 #1 (upstream) with Bosch 15733 and all is well. IMHO Lexus could have put the bung at the side of the pipe instead of up against the firewall in that ridiculous to reach location. Job that should only take 30 minutes took me 2 hours. 
Granted, some of my time was spent attaching the old harness connector to the new sensor.
Granted, some of my time was spent attaching the old harness connector to the new sensor.
08-13-12, 01:03 PM
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bank2 sensor 1 and/or bank 1 sensor 1.
1998 GS300 89K Miles
I have a Check Engine (MIL) light. Connected my OBD II and it reports two occurrences of PO155. My ScanTool.net software shows 0.0V, Sensor 3, Bank 1. But searching on the CL Forum doesn't seem to confirm this description for PO155 MIL. I am finding people talking about Bank 2 Sensor 1 for this code.
From the diagram on the CL DIY Sticky it seems I need to change the pre-cat O2 sensor on the header closest to the firewall.
Can someone please confirm before I spend $80 on an electrical part I can't return? Also, If anyone can confirm the Denso part number and best place to get one online I would really, really appreciate it.
I have a Check Engine (MIL) light. Connected my OBD II and it reports two occurrences of PO155. My ScanTool.net software shows 0.0V, Sensor 3, Bank 1. But searching on the CL Forum doesn't seem to confirm this description for PO155 MIL. I am finding people talking about Bank 2 Sensor 1 for this code.
From the diagram on the CL DIY Sticky it seems I need to change the pre-cat O2 sensor on the header closest to the firewall.
Can someone please confirm before I spend $80 on an electrical part I can't return? Also, If anyone can confirm the Denso part number and best place to get one online I would really, really appreciate it.
thanks you very much.
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