What causes codes P0430 and P0175 at the same time

Question

I have been having problems with idling and shutting off, had plugs o2 sensor bank 2 sensor 1 replaced, MAF sensor cleaned, and also dealer did a fuel and air cleaning that helped and ran fine for 200 miles, but I m getting two codes P0430 and P0175 now, but the car is running fine with no problems yet

Answer 1

P0175 Fuel system too rich

P0430 catalyst system below effiecieny

Running too rich is mainly a mecahnical condition , One inspection that is highly suspectable is the fuel pressure regulator, it is vacuum controled, if the diaphragm  ruptures it wil leak fuel into the intake internally, causing a running  rich condition, Pull the vacuum hose to the fuel regulator if fuel comes out from the diaphragm replace the fuel pressure regulator.

Comments

Do I do this with car running or not

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The engine has to be running and at idle.

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I pulled the vacuum hose off going to manifold and nothing leaks

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Do a fuel pressure test, when fuel pressure is low,the fuel injector does not atomize the spray pattern fuel pressure specification are 43 psi at idle