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GS - 2nd Gen (1998-2005) Discussion about the second generation GS300, GS400 and GS430 (1998 - 2005)

cel on code p0430..need hlep

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Old Dec 30, 2007 | 01:15 PM
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Default cel on code p0430..need hlep

hey fellow member, my check engine came on 2 days ago, i took it to autozone to find out what code it was throwing. After the car was checked for a code, it came up P0430, I asked what code was it, they told me that the caty was at low efficiency or it was the o2 sensor.. Can anyone help confirm what I need to replace and fix...any help would be great
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Old Dec 30, 2007 | 01:42 PM
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A PO430 code is for the Catalyst System Efficiency Below
Threshold (Bank 2). The causes could be:
1. Heated oxygen sensor
2. Three-way catalytic converter
3. Gas leakage on exhaust system
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Old Jan 23, 2011 | 07:12 PM
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Po430 code fix. I battled this for a month and came up with a good cheap fix. I had the po430 code on a 2002 IS300. The cheap fix is to tie both of the bank 1 & 2 sensor 2 input wires at the ecu to the bank one sensor 2 output at the ecu. I used one gold plated butt splice connector at the ecu plug. You must leave both sensors and wiring in place good or bad for the heater load and bank one o2 sensor 2 must be good. You can find the pin out wiring diagram online at o2simulator.com. I feel as though it is a design flaw that everyone over 100K will have to deal with. You can spend thousands on cats and o2's and labor or a 20 cent butt splice connector. Hope this helps everyone.
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Old Jan 23, 2011 | 07:18 PM
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Check to see if you have a leak. I had one at the flange right after the cat and before the downstream o2 sensor. Fixed the leak for $3.50 and the CEL turned off on it's own. Boy was I happy!
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Old Jan 23, 2011 | 07:31 PM
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Po430 code fix. I battled this for a month and came up with a good cheap fix. I had the po430 code on a 2002 IS300. The cheap fix is to tie both of the bank 1 & 2 sensor 2 input wires at the ecu to the bank one sensor 2 output at the ecu. I used one gold plated butt splice connector at the ecu plug. You must leave both sensors and wiring in place good or bad for the heater load and bank one o2 sensor 2 must be good. You can find the pin out wiring diagram online at o2simulator.com. I feel as though it is a design flaw that everyone over 100K will have to deal with. You can spend thousands on cats and o2's and labor or a 20 cent butt splice connector. Hope this helps everyone.
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Old Jan 24, 2011 | 11:31 AM
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ive had this code a lot at work by the time this code comes on.. the previous code p0420 for bank 1 was already on.. ive seen people ignore this and seen that gold plated trick done before but sooner or later the cats get clogged up and all the o2's die.. more than likely your cats are shot but also seen the code on due to exhaust leak.. before its to late order a catalytic converter. very common on gs300's for this code
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