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Roy, import/domestic specialest
Category: Kia
Satisfied Customers: 5862
Experience:  ASE master tech for 40 years
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Kia Sedona 2005 LX with 862323 miles. Bought from dealer and

Customer Question

Kia Sedona 2005 LX with 862323 miles. Bought from dealer and got cheated as same day the check engine light came on when driving from dealer on highway.
I have a check engine light on and the car is losing power and having a rough idle. I checked the code and it says P0430. Catalyst Efficiency Below normal bank 2. Autozone checked Further and said it most likely a Faulty H02S Heated Oxygen Sensor Bank 2.
Cataclean, but the light did not go off.
With half a tank I put Cataclean and drove for 15 miles. Rough idle went and seem to go little smoother. I know it says you are suppose to use it at 1/4 tank but had 1/2 tank left. Can I use it again
2) Where is this sensor located and is it easy for me to replace it.
3) would seaform help in anything. I was thinking of applying to gas tank as second owner did not take care of car well.
4. After it replaced how do I reset the code.
Submitted: 3 months ago.
Category: Kia
Expert:  david craig replied 3 months ago.

Hi Im David, thanks for visiting the site. that sensor is not going to fix the issue. you have a clogged catalytic converter. you will need to have a back pressure test done on that bank to verify that it is clogged, but if you are losing power, its clogged.

Expert:  david craig replied 3 months ago.

can I help with anything else. I will give you the replacement procedure of the sensor if you still want it, but its not going to fix the problem.

Customer: replied 3 months ago.
The Cataclean actually help resolve the powerloss and rough idle. I did it with Half gas tank when it I was not sure if I could pour a second bottle in with 1/4 tank not sure if it will do harm.Thanks
Expert:  david craig replied 3 months ago.

very good. so it was clogged. that stuff works fairly well but its a 50/50 shot. did you reset the check engine light?

Expert:  Roy replied 3 months ago.

ok, the 430 code indicates that the precious metals inside the cat are worn out and the cat needs to be replaced. the O2 sensor will not do anything for the issue.

the additive you used may have help unclog an injector that may have had dirt on the pindle. that would explain the rough idle you had.

there is no additive that will unclog a cat converter. if you had a clogged converter, you would have a power loss more at highway speed than anywhere else as it effects breathing of the engine


Expert:  Roy replied 3 months ago.

are you there??