P0420 & p0430
11-02-17, 12:11 PM
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P0420 & p0430
Whats up fellas... Alright my ALT went out about 2 weeks ago left me broken down. Had it towed to the Dealership they replaced the ALT and battery. 1 day later the CEL ,VSC and others popped up. They looked at it and its a P0420 and a P0430 code. I know its Below Threshold for the cats. The dealership want to replace the CATS for $3200. Thats seems like cutting of the head for a headache. I did reset the code and it popped back up yesterday. Also ive gone from 17.1 to 15.1 mpg
So i have a few questions.
1) In what order should i have this address
2) Does anyone know part #
Im NOT mechanically inclined so ill be leaning on my Mech to do the work. But would like to know what im up against from the begining.
Thanks
J'ean
So i have a few questions.
1) In what order should i have this address
2) Does anyone know part #
Im NOT mechanically inclined so ill be leaning on my Mech to do the work. But would like to know what im up against from the begining.
Thanks
J'ean
11-03-17, 06:13 AM
#3
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The gas cap probably needs replacing anyway due to age, but the noticeable drop in mileage does point to bad sensors.
You don't need the dealer to do this service - any decent shop can replace them. Just make sure your mechanic orders the Denso brand. This will be cheaper than dealer parts. But if you want factory parts -
If you have a very early GX, there are three - one front, and two rear. The majority of GX's have four - two front (p/n 8946535690) and two rear (p/n 8946560200 on the left, and p/n 8946560250 for the right)
https://www.lexussouthatlantaparts.c...rimLevel=19100
Chip H.
You don't need the dealer to do this service - any decent shop can replace them. Just make sure your mechanic orders the Denso brand. This will be cheaper than dealer parts. But if you want factory parts -
If you have a very early GX, there are three - one front, and two rear. The majority of GX's have four - two front (p/n 8946535690) and two rear (p/n 8946560200 on the left, and p/n 8946560250 for the right)
https://www.lexussouthatlantaparts.c...rimLevel=19100
Chip H.
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Tdoll (11-04-17)
11-16-17, 04:40 AM
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The gas cap probably needs replacing anyway due to age, but the noticeable drop in mileage does point to bad sensors.
You don't need the dealer to do this service - any decent shop can replace them. Just make sure your mechanic orders the Denso brand. This will be cheaper than dealer parts. But if you want factory parts -
If you have a very early GX, there are three - one front, and two rear. The majority of GX's have four - two front (p/n 8946535690) and two rear (p/n 8946560200 on the left, and p/n 8946560250 for the right)
https://www.lexussouthatlantaparts.c...rimLevel=19100
Chip H.
You don't need the dealer to do this service - any decent shop can replace them. Just make sure your mechanic orders the Denso brand. This will be cheaper than dealer parts. But if you want factory parts -
If you have a very early GX, there are three - one front, and two rear. The majority of GX's have four - two front (p/n 8946535690) and two rear (p/n 8946560200 on the left, and p/n 8946560250 for the right)
https://www.lexussouthatlantaparts.c...rimLevel=19100
Chip H.
Thanks agian!!!!
01-29-21, 01:05 PM
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Did you end up replacing the cats after all?
I had the exact same thing happen - alternator died on a road trip and took the battery with it. Had them replaced and about 500 miles later I got P0420 and P0430.
I had the exact same thing happen - alternator died on a road trip and took the battery with it. Had them replaced and about 500 miles later I got P0420 and P0430.
02-01-21, 05:36 PM
#6
Add cheaters on the Oxygen Sensors. I had this same issue with my LS460 and added two cheaters versus $3K in cats and she's running like new. Your cats could be running 1% below the minimum threshold and the code will flash.
Here is a link
Here is a link
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