Code P0430 and P0420 on my 06 gs300 AWD

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07-09-18, 01:21 PM

bdpride04

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Code P0430 and P0420 on my 06 gs300 AWD

Just got the codes, does it really mean my car needs new cat? Anyone had those codes and fixed them? If cat change is the only option, where can i buy one from? Dont wqnt to go to dealership

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07-09-18, 03:22 PM

RXGS

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For me it was an exhaust leaks at the flange underneath the driver and passenger seats. didn’t come on on the highway only in the city. Went to an exhaust shop, paid like$100 problem solved

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07-10-18, 04:12 AM

bdpride04

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Quote:

Originally Posted by RXGS

For me it was an exhaust leaks at the flange underneath the driver and passenger seats. didn’t come on on the highway only in the city. Went to an exhaust shop, paid like$100 problem solved

thanks will take it to muffler shop

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07-21-18, 09:39 AM

bdpride04

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funny thing is i just cleared the code and it is off for like a week now. not sure why would that happen. if the cat was bad wouldn't it come back? i drove around 500 miles so far. what am i missing?

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07-22-18, 10:26 AM

sha4000

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Quote:

Originally Posted by RXGS

For me it was an exhaust leaks at the flange underneath the driver and passenger seats. didn’t come on on the highway only in the city. Went to an exhaust shop, paid like$100 problem solved

This is the most likely issue. Had these on my 400 and just applied exhaust cement over the flanges and problem solved.

Last edited by sha4000; 09-16-18 at 02:46 PM.

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07-26-18, 05:16 AM

bdpride04

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Quote:

Originally Posted by sha4000

This is the most likely issue. Had these on my 400 and just appled exhaust cement over the flanges and problem solved.

even though code is off now about to take it to muffler shop to check out. Thanks

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07-26-18, 11:12 AM

ibidu1

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While at the muffler shop you might want to have them remove all the tin covering the exhaust tubes on the mid pipe. That tin with the fabric lining inside traps moisture and rusts out our tubes. This is only on awd's best to remove it or you will get other leaks down the road.