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Had several EVAP smoke tests performed to address emissions

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Had several EVAP smoke tests performed to address emissions problem. Now getting the P0430 CEL code. Before smoke test and repairs for EVAP leak, didn't get the P0430 catalytic converter efficiency below threshold bank 2

Hello. Welcome to Just Answer. Please allow me to assist you. A P0430 code does not mean you have a bad catalytic converter. Most likely, you have a non-Toyota Air-Fuel sensor or a Non-Toyota Oxygen sensor installed. Would either of these be the case?

Customer: replied 10 months ago.
Oddly enough when I perform an engine scan, the IM Readiness gives a green light the catalytic converter is good. But, I'm confused as to why my cel light would come on.

Assuming you sensors are genuine Toyota, the other most common causes for a P0430 is a leaking intake manifold gasket, worn spark plugs, dirty fuel injectors, and a stretched timing belt. More often than not, though, non-Toyota sensors cause this code because they are not transmitting what the computer needs to see to pass the data that is being input.

Customer: replied 10 months ago.
I actually don't know if the oxygen sensors on the bank 2 are Toyota or not.

I would replace the sensors before I spent any money on a catalytic converter. If your scope does an oscilloscope function, look at the waveform of the sensor. If both waveforms match, the cat is bad.

I would replace the A-F and O2 sensors before I spent any money on a catalytic converter. If your scanner does an oscilloscope function, look at the waveforms of the sensors. If both waveforms match, the cat is bad

Customer: replied 10 months ago.
Thanks. Just for edification what does a-f stand for?

Air-Fuel. Sorry, mechanic talk.

The Air-fuel sensor measure what comes out of the engine; the oxygen sensor measures what comes out of the catalytic converter.

Customer: replied 10 months ago.
Change the two O2 sensors on the catalytic converter?
Customer: replied 10 months ago.
What about aftermarket catalytic converters? Is it okay to install aftermarket converters?

Not really. The computer is designed to see specific data from the rear (oxygen ) sensor. If the cat is aftermarket, the dat that the rear sensor is sending to the compute r is not good data. Common for aftermarket converters to cause the check engine light to come on.

Customer: replied 10 months ago.
Would a used catalytic converter for the same engine be better then aftermarket if new Toyota one is not affordable?

That would not be a bad idea; as long as the supplier guaranteed it was OK

Customer: replied 10 months ago.
In essence a warrantied catalytic converter. Also, how would I be able to tell if there's an exhaust leak from the intake manifold? I just had 3 EVAP smoke tests performed; and would think that would been observed?

A smoke test may not reveal an intake manifold gasket leak. The pressure of the smoke is not as great as the draw of the pistons. A good test for an intake would be to get a can of carburetor cleaner. Spray some into the air intake above the air filter with the engine running. Note the change in odor of the exhaust coming out of the tailpipe. Then close the air filter box and spray the intake where it fits onto the cylinder head withe the engine running. If you smell the same odor, the intake is leaking

Customer: replied 10 months ago.
Also, the Bank 2 is at the front of the engine? The initial catalytic reaction takes place within the from the front or back? I ask because at one time someone during an oil change did not tighten my oil filter & used improper non-synthetic oil?
Customer: replied 10 months ago.
Is replacing an air intake gasket a less intensive repair?

Bank 2 is the side of the engine with the #2 spark plug. On a V6 Camry, this would be the front side of the engine. An intake manifold gasket replacement is not an 'easy' job, but is way less than a new converter. All of the reaction takes place insie the converter. That is why the Oxygen sensor is there; to measure and transmit what the converter is doing. The rear (oxygen) sensor is there purely for emission controls. It really does nto change what the air-fuel mixture is doing; the front (air-fuel) sensor is responsible for the that

Customer: replied 10 months ago.
My car was just in the service shop, and he informed me of the P0430 code; which was not their before the smoke tests. Upon having to take my car back a second time with only P0441, P0442, & P0446 being present. The service shop brought the P0430 to my attention but did not suggest the items you've mentioned as potential causes.

The P0441-442-446 is probably a leak due to a flattened o-ring on the gas cap. I would get a can of BG 44-k and put it into the tank and drive it. The BG 44-K product will clean the soot (if any) inside the converter, clean the injectors, and remove carbon deposits from the faces of the valves. I would be doing that before any P0420 or p0430 code parts replacements. (assuming the sensors are genuine)

Customer: replied 10 months ago.
What about cataclean?

I have never heard of that product. We use BG 44-K. Is is phenomenal stuff.

Customer: replied 10 months ago.
Thanks. If I'm correct the OEM for the a-f & O2 sending is Denso


Customer: replied 10 months ago.
Thanks allot.

Thanks for choosing Just Answer. It was a pleasure to assist you. I trust my input is satisfactory and meets your expectations. A positive rating for my assistance on your request would be greatly appreciated; thanks again and have a great day

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Customer: replied 9 months ago.
Have a question about P0172 & P0175 codes. Received these codes after changing PCV valve and wrapping PCV connector hose with high thermal silicon tape
Customer: replied 9 months ago.
Have also been experiencing car Toyota Camry will not start after fueling. Which transpired after I had my car serviced for an EVAP leak; which is also still present.
Customer: replied 9 months ago.
Generating the same codes P0441, P0442, & P0446

Let's look at the metal part of the filler neck, where the fuel cap fits. Does it have spots of rust on it?

P0172 and P0175 are codes that indicate that either the engine is not admitting enough air (ie clogged air filter or the timing is off).


the fuel injectors are dirty and spraying an abnormal cone of atomized fuel. You also might be getting wet fuel into the intake thru the evaporative emission system. This is common when the tank is filled clear full. This will also give you the 440 441 and 446 codes

Customer: replied 9 months ago.
I replaced the air filter, but I thought those codes mean I'm running rich now

You can also get P0172/0175 from faulty ignition coils.

Customer: replied 9 months ago.
I replaced the ignition coils last summer with denso & Bosch spark plugs

Bosch plugs are not good for this engine. Replace them with Nippondenso.

Customer: replied 9 months ago.
I'm looking at the gas fill intake, removed gas cap
Customer: replied 9 months ago.
Also, I don't have access to the fuel filler neck.

The rust spots I am concerned with will be where the cap fits.

Customer: replied 9 months ago.
Also, I've only been filling my fuel tank to 3/4 so as to allow the EVAP tests to run on the car.

It would be nice to know the total amount of fuel you can put into the tank. Sometimes. the tank draws shut a bit, or something may have impacted the bottom of the tank. Eith of these conditions will not allow the proper fuel fill. IE when it is 3/4 full, it is really allowing fuel to get into the evap system. You also might need a new charcoal canister assembly.

Customer: replied 9 months ago.
A new charcoal canister would address the EVAP leaks and the P0172 & P0175 since it's a closed loop?
Customer: replied 9 months ago.
It's about 19.2 gallons

if you are getting excess fuel vapors thru the canister, you will get a P0172 & a P0175. Once wet fuel gets into the charcoal, the canister is no longer operational. This sounds like you need to replace the charcoal canister.

Customer: replied 9 months ago.
Do you know what would cause excess fuel to enter the charcoal canister cause I don't double tap when I fill. I stop after getting the indicator. The canister is a dorman
Customer: replied 9 months ago.
Is their an ideal canister?
Customer: replied 9 months ago.
replacing my PCV valve with the OEM Toyota & wrapping the PCV hose which had a leak near the clamp would not throw those codes.

No. Not at all. The PCV and wrapping would not cause the codes. Now, it is possible the PVC valve you installed is not functioning properly.

Dorman is not good, sorry. You want genuine Toyota parts. In fact, a lot of what you find in parts stores are not good for this car. Plugs, coils, gas caps, canisters, converters...all are inferior to the genuine parts. We see this all the time in the shop. The parts stores sell it cheaper because that is exactly what is is. Cheaper. As in not as good as original.

Customer: replied 9 months ago.
How would I know if the PCV Valve may have an issue?

If you take it out and the engine idle does not change

Customer: replied 9 months ago.
Just seem strange I'd get new codes after changing the air filter & PCV valve
Customer: replied 9 months ago.
Okay. I'll check.

I assume the air filter is not a factory replacement. The Mass sir sensor on this car expects to see a specific volume of air passing. That predicates the need for a factory air filter. Back in the old days, with carbs, the more air you had the better. Today, with precise fuel management, everything needs to work as designed. You add Bosch plugs, parts store coils and and air filter, you are bypassing the original design.

Customer: replied 9 months ago.
Gotcha it's not a Toyota air filter, oreilys

thought so. I would replace all of the non-toyota parts

Customer: replied 9 months ago.
Will do. I didn't think the air filter on the airbox would be an issue. Let me also ask what about car not starting immediately after refueling at the gas station. Seemed strange my car didn't have this issue after smoke test.
Customer: replied 9 months ago.
Also how does the charcoal canister affect the P0442 & P0446 codes?

If the car is not starting after fueling, it is most likely that you are getting wet fuel into the evaporative emission line. In short, you are putting a lot of gasoline fumes intot he intake manifold. This causes a rich mixture to be present and this fouls the plugs.

Customer: replied 9 months ago.
The fix would be a new charcoal canister

That would be recommended. Once it gets wet inside with fuel, it is no longer any good.

Customer: replied 9 months ago.
Do you know what would cause this in the first place?

Either a malfunctioning evaporative emission vacuum switching valve or the line that draws vapor for,m the tank is compromised and is drawing wet fuel. The vacuum switching valve is under the hood, it is attached to a black rubber hose that leads to the intake manifold; it should have a green plastic label on it.

Customer: replied 9 months ago.
Is that vacuum switching valve on the air box container? Or the VSV on the vacuum rail? Does the line that draws vapor from the gas tank have some type of fitment to prevent the canister from drawing wet fuel?

The valve is close to the firewall. Green label with a fitting. This is where they smoke test. They may have damaged this valve when they did the smoke test. The tank has a tube that draws the vapor form the top of the tank. If it gets dislodged, it will suck fuel, not vapor.

Customer: replied 9 months ago.
The shop placed a non Toyota (Dormans) vacuum valve on the back of my air box sits close to the driver side firewall & closes valve to the green EVAP air port, which I will replace. On the 2nd service for th EVAP leak, the gas tank was dropped to install an overflow part with the rubber grommet. Quite possibly, the fuel to charcoal canister hose was compromised.

Without knowing exactly what they did with this overflow valve, and why, I would say that this is the cause of all of your problems. You should not need an "overflow valve". You probably need a tank and a canister.

Customer: replied 9 months ago.
They said I had an EVAP leak at the overfill valve, so they had to replace. It sounds like I should replace the EVAP port they placed on.

These cars do not have an "overflow valve". It has a vent line that runs from the tank up the side of the main fuel fill tube. They probably mistook the part of the line that the canister connects to that tank as that. That is not good if that is so. That means they were guessing.

Customer: replied 9 months ago.
Yeah, I think so. They weren't a Toyota mechanic. What would you recommend as a final solution?

I am thinking replace the tank and the canister.

Customer: replied 9 months ago.
What would replacing the gas tank resolve?

if the vapor line has come loose where it is soldered on the inside top of the tank, your replacement canister (if you do not replace the tank) will be rendered inoperative the first time wet fuel gets into it.

Customer: replied 9 months ago.
I'm looking at my Toyota Part No.: 77001-33110 and wondered how would/could I inspect the fuel tank to determine if the soldiered inside vapor line of the fuel tank is bad? Before making such an expensive purchase for a new gas tank?

It is rather difficult to resolder a loose vent line tube. One cannot 'see' it to do the work very well. It is worth a try, assuming you can find someone who is skilled enough to do this. In my shop, we would decline this resolder request, because we cannot guarantee the repair will hold.

Customer: replied 9 months ago.
Sorry, I wasn't asking about re-soldiering. I was asking if it's possible to view the vapor line in the gas to tank to determine if it is in fact bad?

Pull the sending unit out and use an articulated mirror in conjunction with a good light to see inside the top of the tank.

Customer: replied 9 months ago.
Have another question. Car won't start after refueling. Replaced charcoal canister with a genuine Toyota OEM canister. And, can't seem to understand how it would not start. Prior to smoke tests in an attempt to resolve EVAP issues, car won't start after refueling