Not Again!! Code P0420 :(
Not Again!! Code P0420 :(
Well, after the general consensus that i needed my Cats replaced because of code P0420 (Catalyst Efficiency Below Threshold Bank 1) which the Lexus dealership and independent shop told me, i had 2 OEM Lexus Cats put on by a muffler shop with new OEM gaskets. Ecu was reset. This was about 2 or 3 weeks ago.
Yesterday i'm driving around, light pops back on, get the code scanned and its code P0420 (Catalyst Efficiency Below Threshold Bank 1)! So i guess my Cats were never the problem
Please tell me where to go from this and how i can resolve this. I am still noticing a loss of power so obviously the issue is still not resolved.
I know you guys told me before to replace all the oxygen sensors before i spend money on Cats, but a few people told me that if it was an oxygen sensor, it would be a different code and most likely it was the Cats. So, i didn't feel like throwing oxygen sensors at the car and still needing to replaced the Cats but it looks like i'm screwed regardless. Please help!!!
Yesterday i'm driving around, light pops back on, get the code scanned and its code P0420 (Catalyst Efficiency Below Threshold Bank 1)! So i guess my Cats were never the problem
Please tell me where to go from this and how i can resolve this. I am still noticing a loss of power so obviously the issue is still not resolved. I know you guys told me before to replace all the oxygen sensors before i spend money on Cats, but a few people told me that if it was an oxygen sensor, it would be a different code and most likely it was the Cats. So, i didn't feel like throwing oxygen sensors at the car and still needing to replaced the Cats but it looks like i'm screwed regardless. Please help!!!
Yes a bad sensor can cause power loss if it's signaling the ECU inaccurate information.
The sensor that's signaling the code is on the driver side. It's located after the catalytic converter. You can have a shop monitor the sensor's activity to see whether they're working or not.
The sensor that's signaling the code is on the driver side. It's located after the catalytic converter. You can have a shop monitor the sensor's activity to see whether they're working or not.
Yes a bad sensor can cause power loss if it's signaling the ECU inaccurate information.
The sensor that's signaling the code is on the driver side. It's located after the catalytic converter. You can have a shop monitor the sensor's activity to see whether they're working or not.
The sensor that's signaling the code is on the driver side. It's located after the catalytic converter. You can have a shop monitor the sensor's activity to see whether they're working or not.
Was that correct and the only one i need?
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https://www.clublexus.com/forums/gs-...-seonsors.html
https://www.clublexus.com/forums/per...placement.html
https://www.clublexus.com/forums/gs-...n-sensors.html
the correct Denso part numbers are:
(1,2,3 precat) Bank 1 Sensor 1: 234-4048
(1,2,3 postcat) Bank 1 Sensor 2: 234-4626
(4,5,6 precat) Bank 2 Sensor 1: 234-4630
(4,5,6 postcat) Bank 2 Sensor 2: 234-4603
Got mine off amazon and they qualified for free 2 day shipping. Paid around $65 a piece and actually recieved them in 2 days.
https://www.clublexus.com/forums/per...placement.html
https://www.clublexus.com/forums/gs-...n-sensors.html
the correct Denso part numbers are:
(1,2,3 precat) Bank 1 Sensor 1: 234-4048
(1,2,3 postcat) Bank 1 Sensor 2: 234-4626
(4,5,6 precat) Bank 2 Sensor 1: 234-4630
(4,5,6 postcat) Bank 2 Sensor 2: 234-4603
Got mine off amazon and they qualified for free 2 day shipping. Paid around $65 a piece and actually recieved them in 2 days.
https://www.clublexus.com/forums/gs-...-seonsors.html
https://www.clublexus.com/forums/per...placement.html
https://www.clublexus.com/forums/gs-...n-sensors.html
the correct Denso part numbers are:
(1,2,3 precat) Bank 1 Sensor 1: 234-4048
(1,2,3 postcat) Bank 1 Sensor 2: 234-4626
(4,5,6 precat) Bank 2 Sensor 1: 234-4630
(4,5,6 postcat) Bank 2 Sensor 2: 234-4603
Got mine off amazon and they qualified for free 2 day shipping. Paid around $65 a piece and actually recieved them in 2 days.
https://www.clublexus.com/forums/per...placement.html
https://www.clublexus.com/forums/gs-...n-sensors.html
the correct Denso part numbers are:
(1,2,3 precat) Bank 1 Sensor 1: 234-4048
(1,2,3 postcat) Bank 1 Sensor 2: 234-4626
(4,5,6 precat) Bank 2 Sensor 1: 234-4630
(4,5,6 postcat) Bank 2 Sensor 2: 234-4603
Got mine off amazon and they qualified for free 2 day shipping. Paid around $65 a piece and actually recieved them in 2 days.
Was this for a GS300? The part numbers are different for a GS430.