p0430 code ... which cat is bad?
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Driver School Candidate
Joined: Dec 2010
Posts: 3
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From: pa
p0430 code ... which cat is bad?
02 IS300 w/ 130k miles - EVERYTHING is stock
Over the summer I replaced both the header and ypipe with parts from ebay (salvage cars). Initially I had a p0420 code and took care of everything along with 3 of the 4 o2 sensors. The only o2 sensor i didnt replace was the B2S1 sensor due to it arriving late from California. Fast forward to earlier this week. Now I'm getting a p0430 code! I understand this could be an o2 sensor going bad, if so would that explain maybe the B2S1 sensor since I never replaced it?
If it is indeed a bad cat, would it be one of the two in the manifold or the one on the ypipe?
Over the summer I replaced both the header and ypipe with parts from ebay (salvage cars). Initially I had a p0420 code and took care of everything along with 3 of the 4 o2 sensors. The only o2 sensor i didnt replace was the B2S1 sensor due to it arriving late from California. Fast forward to earlier this week. Now I'm getting a p0430 code! I understand this could be an o2 sensor going bad, if so would that explain maybe the B2S1 sensor since I never replaced it?
If it is indeed a bad cat, would it be one of the two in the manifold or the one on the ypipe?
10th Gear
Joined: Sep 2001
Posts: 12
Likes: 2
From: NJ
P0420, p0430
Lucky,
P0430 refers to the bank 2 catylist. On the IS300, thats the cat which takes care of cylinders 4,5, and 6 (the second one on the header). Before replacing any sensors, make sure you have NO exhaust leaks at the header/exhaust pipe connection, as any leak could cause the code to set.
P0430 refers to the bank 2 catylist. On the IS300, thats the cat which takes care of cylinders 4,5, and 6 (the second one on the header). Before replacing any sensors, make sure you have NO exhaust leaks at the header/exhaust pipe connection, as any leak could cause the code to set.
Thread Starter
Driver School Candidate
Joined: Dec 2010
Posts: 3
Likes: 0
From: pa
What's the code for the ypipe's cat? Bummer as I replaced both the header and the ypipe with parts from salvage cars. I'm hoping that the B2S1 is the reason why that code keeps appearing. it's the only o2 that wasn't replace.
Definitely check for leaks. Did you replace the gaskets?
P0430 is bank 2(cyl 4,5,6) catalyst is going bad. Thats the headers closest to the firewall. Sorry bro, wish it was that B2S1 sensor.
Here is a code list...
http://my.is/forums/f87/obd-codes-list-326733/
P0430 is bank 2(cyl 4,5,6) catalyst is going bad. Thats the headers closest to the firewall. Sorry bro, wish it was that B2S1 sensor.
Here is a code list...
http://my.is/forums/f87/obd-codes-list-326733/
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Joined: Mar 2014
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From: Florida
I had those codes two weeks ago.. One of the two up front car broke in pieces and got clogged at the cat in the back so I bought the who exhaust from a parted is300 and got the sensors with it.. Complete exhaust cost me 250 and it was a cheaper fix then buying a brand new one for getting the cars replaced. So start with a leak first if nothing. At night take the car for a spin and get it high rpm's then quickly in a dark area check all three cats if they glow red. That's a sign of a bad cat. If it's the one of the two up front replace it quick or you'll have two bad cats if you don't!
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