Annoying P0430 need to solve it. (1 Viewer)

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i forgot to mention that i tried to use Marvel Mystery oil on gas tank once and the code had disappeared for awhile, also, cleaning my K&N air filter made it disappear for awhile as well, what can you conclude from those experiences?
 
i forgot to mention that i tried to use Marvel Mystery oil on gas tank once and the code had disappeared for awhile, also, cleaning my K&N air filter made it disappear for awhile as well, what can you conclude from those experiences?
I used similar to what you tried, I tried a bottle of CataClean, followed their specific instruction of pouring it with 1/8 to 1/4 only left in the fuel gauge-didn’t do anything the CEL P0430 was their never left.

@2001LC yes that’s correct on the stalling problem just a few months ago. The new denso fuel pump fixed that heat soak problem leading to engine stalling. Also replaced the intake manifold assembly gasket using OEM new ones on both sides. Retightened the valve cover bolts to oe spec torque -those were loose.

You said you replaced the catalytic converter, what type/kind/brand did you use? Any link to it? This P0430 is becoming very popular with VVTi 2UZs..
 
a mechanic checked for exhaust leak and he couldn't hear anything. he said that i dont have an exust leak, i will need to check for small leak around O2s with vacuum methods and soapy water and will switch O2s sides.

in term of water leak, i have checked lately and i dont see any coolant is missing ( since 2-3 months ago when i had to add couple ounces). i guess with our unbearable hot climate during summer (reaches 120F), some coolant evaporates. since the weather is cool now, i dont lose any coolant, is that possible or should i dig more?
 
a mechanic checked for exhaust leak and he couldn't hear anything. he said that i dont have an exust leak, i will need to check for small leak around O2s with vacuum methods and soapy water and will switch O2s sides.

in term of water leak, i have checked lately and i dont see any coolant is missing ( since 2-3 months ago when i had to add couple ounces). i guess with our unbearable hot climate during summer (reaches 120F), some coolant evaporates. since the weather is cool now, i dont lose any coolant, is that possible or should i dig more?

Did you check the rear crossover pipe? I had the same trouble, very minor leak. The o-ring at the crossover pipe was just weeping.
 
I may be late to the show, but a new gas cap fixed my p0430code 10k miles ago.

Also, what's that shiit wrapped and zip tied?
This fixed mine also. I also noticed that when I went to refill my tank, I had a large amount of air come out. I got a new cap the next day and my issue immediately went away.
 
i forgot to mention that i tried to use Marvel Mystery oil on gas tank once and the code had disappeared for awhile, also, cleaning my K&N air filter made it disappear for awhile as well, what can you conclude from those experiences?
Did you clear the P0430 code after using MMoil & cleaning K&N air filter, then P0430 returned?
Or did the check engine light go off by itself without clearing code?

I used similar to what you tried, I tried a bottle of CataClean, followed their specific instruction of pouring it with 1/8 to 1/4 only left in the fuel gauge-didn’t do anything the CEL P0430 was their never left.

@2001LC yes that’s correct on the stalling problem just a few months ago. The new denso fuel pump fixed that heat soak problem leading to engine stalling. Also replaced the intake manifold assembly gasket using OEM new ones on both sides. Retightened the valve cover bolts to oe spec torque -those were loose.

You said you replaced the catalytic converter, what type/kind/brand did you use? Any link to it? This P0430 is becoming very popular with VVTi 2UZs..
The CAT I used on bk1 (DS P0420), Davico 17194. I did so to match, what Midas installed 4K miles earlier on Bk 2 (PS P0430), which was before I got involved with this rig.

Davico does not sell retail. To my door, I was right around $300 from retailer. I'm having issue with customer service of both manufacture and retailer I purchased this Davico from. So I'll not post a link. A dumb issues really. But I'm shocked at how they've handle it. Makes me wonder about how they'd handle warranty. But all these aftermarket CATs, are 5 yr or 50K miles warranty. They must be tested and approved to EPA standards. They are all consider a lifetime product, OEM or aftermarket. They do not just go bad if well made. Something external effects them.

Davico comes with plug (plug was missing in one I bought) for second O2 hole and two gaskets for pipes/flanges. It's universal as to PS or DS, that's why it has two O2 holes. I purchased a new 18mm plug (automotive drain plug), two O2 18mm crush washers (no one but me replaces those), two OEM gaskets (I like them better), 3 OEM nuts for upstream flange studs of exhaust manifold (FSM has as none reusable), Two nut & bolts (FSM has as none reusable) for down stream pipe flange to muffler.

The Davico replacement CAT internal ceramic material, has a slightly smaller diameter and are shorter in length than OEM. They have a heat shield on top only. I'd like to see a full heat shield. One could wield on brackets and fit OEM shielding. But not a big deal to me either way.

The CAT Midas installed did end up getting a P0430 again. You can read about in the link I provided early and here in this thread. You'll see reading the above link, Midas totally messed up every single point they touched on installing the PS CAT. I've correct the issues Midas created, and I reinstalled the CAT. Some stuff they messed up I've not yet posted. So far no more CAT code. But they touched the O2's probe, so it may have a limited life.

I had pulled that PS CAT Midas installed, just to see what was going on. I thought perhaps they did not correct upstream issues or run 44k, seafoam, CatClean, etc cleaner through engine before install. To not clean upstream carbon & gunk before install, it may re-clogged. I talked with them and they did not do anything corrective. I had run cleaners 44k, seafoam, CatClean and repair upstream stuff, before I installed DS CATs. So I thought possible I re-clogged the PS CAT Midas installed.

I felt, since it was replaced recently. It would be easy to remove. I also had all parts I needed to reinstall by the book. So I pulled it off.

Man was I pissed off. I've seen so many bad job, but this one was a mess. You'd think exhaust is one thing Midas would do right. Hey they were once called Midas Muffler.. No wonder the P0430 DTC came back.
 
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@2001LC that sucks! I mean that’s the worst feeling ever you shelled out a good amount of hard earned money for repair only to cause more problems and of course more $$$! I am still researching as to what step I would take:
-aftermarket CAT (DEC manufacturer)
-oem direct bolt-on style
-but I’m worried about the way the pipe was bent
F3DC3FCB-FAEE-4648-89F1-418E0A4926BC.jpeg


Or go CAT-less:
- better performance as restrictive features of the OE CAT is eliminated
- cut and weld type -local muffler shop who “seem” to know a thing or two about doing these types of repairs: I will request though for at least a MIG welding or of they have TIG which is better.
- downside is possibility of still have the dreaded CEL P0430 DTC
61B8F1D3-BF3D-4780-8E0D-E8A1202FE701.jpeg
7970EB8F-E029-4DF5-AEE0-4CDCC0239152.jpeg


I hope a fellow mudder can chime in on their experience on any of these products or how they were able to fix their P0430 problem, this thread is good index for future reference.
 
To be clear I did not pay for or commission Midas to do the first install. That was before my time by PO!

Even OEM narrows in bend. Notice the heat shield.
001.JPG
 
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Did you clear the P0430 code after using MMoil & cleaning K&N air filter, then P0430 returned?
Or did the check engine light go off by itself without clearing code?


The CAT I used on bk1 (DS P0420), Davico 17194. I did so to match, what Midas installed 4K miles earlier on Bk 2 (PS P0430), which was before I got involved with this rig.

Davico does not sell retail. To my door, I was right around $300 from retailer. I'm having issue with customer service of both manufacture and retailer I purchased this Davico from. So I'll not post a link. A dumb issues really. But I'm shocked at how they've handle it. Makes me wonder about how they'd handle warranty. But all these aftermarket CATs, are 5 yr or 50K miles warranty. They must be tested and approved to EPA standards. They are all consider a lifetime product, OEM or aftermarket. They do not just go bad if well made. Something external effects them.

Davico comes with plug (plug was missing in one I bought) for second O2 hole and two gaskets for pipes/flanges. It's universal as to PS or DS, that's why it has two O2 holes. I purchased a new 18mm plug (automotive drain plug), two O2 18mm crush washers (no one but me replaces those), two OEM gaskets (I like them better), 3 OEM nuts for upstream flange studs of exhaust manifold (FSM has as none reusable), Two nut & bolts (FSM has as none reusable) for down stream pipe flange to muffler.

The Davico replacement CAT internal ceramic material, has a slightly smaller diameter and are shorter in length than OEM. They have a heat shield on top only. I'd like to see a full heat shield. One could wield on brackets and fit OEM shielding. But not a big deal to me either way.

The CAT Midas installed did end up getting a P0430 again. You can read about in the link I provided early and here in this thread. You'll see reading the above link, Midas totally messed up every single point they touched on installing the PS CAT. I've correct the issues Midas created, and I reinstalled the CAT. Some stuff they messed up I've not yet posted. So far no more CAT code. But they touched the O2's probe, so it may have a limited life.

I had pulled that PS CAT Midas installed, just to see what was going on. I thought perhaps they did not correct upstream issues or run 44k, seafoam, CatClean, etc cleaner through engine before install. To not clean upstream carbon & gunk before install, it may re-clogged. I talked with them and they did not do anything corrective. I had run cleaners 44k, seafoam, CatClean and repair upstream stuff, before I installed DS CATs. So I thought possible I re-clogged the PS CAT Midas installed.

I felt, since it was replaced recently. It would be easy to remove. I also had all parts I needed to reinstall by the book. So I pulled it off.

Man was I pissed off. I've seen so many bad job, but this one was a mess. You'd think exhaust is one thing Midas would do right. Hey they were once called Midas Muffler.. No wonder the P0430 DTC came back.
No. It went off by itself.
even last night after driving 250miles, I turned off the car then turned it on then it was gone.
 
Is it safe to say I have no problems with AFs, O2s nor catalyst converter with these data?

4606363F-578B-43C4-9501-9BF3E4B74D99.jpeg


7D3B2C19-B912-4023-9FA7-2912D850E0A7.jpeg


EE70DFB9-424C-45F6-8E94-773297BDDC53.jpeg
 
Interest CEL going out.

Do you have CAT Temps. After warm up Run at idle, and then at 2K RPM record CAT temps at start of 2KRPM and after two minutes held at 2K RPM..

Be interesting to see what happens when you swap O2s.

Have you ever had the intake gasket replaced?
Have you done a compression test?
 
To be clear I did not pay for or commission Midas to do the first install. That was before my time!

Even OEM narrows in bend. Notice the heat shield.
View attachment 2133944
ok ok both are crush bent. the heat shield on the aftermarket is welded? for decoration only? Lol!
the oem heat shield has 4 bolts on it
 
Interest CEL going out.

Do you have CAT Temps. After warm up Run at idle, and then at 2K RPM record CAT temps at start of 2KRPM and after two minutes held at 2K RPM..

Be interesting to see what happens when you swap O2s.

Have you ever had the intake gasket replaced?
Have you done a compression test?
I will swap O2 sensor when I get a chance.
no never had the intake gasket replaced.
compression test will be hard to find some one will do it in this country, but as I stated before , I know for a fact that my issue is simple fix like gas cap( looking to buy new one this week) not O2s or cat.
@2001LC after seeing your post about intake gasket coolant leak, I got concerns about mine. And possibility I have same thing.
 
Your coolant temp looked okay, but just a tad high at 192F (depending on OAT (outside Air Tempo), may by just right, if you were just idling.

The intake gasket on the VVT shrinks over time. Typically I see oily/crud build-up come up the sides of intake tubes from heads. Also the oily/crud will be on head covers coming from where intake manifold seals at head. Yet the lower part head-cover (gasket) is dry (clean). This is a sign intake gasket are leaking when cold. If leaking it is best to replace. Or a vacuum leak may be present. They do most time seal themselves, as engine reaches operating temp. But still we don't want any vacuum leaks at any time. Depending on mileage it's a good time to do the starter if replacing that gasket.
Look at the last two picture in post #164, than read on. Some VVT show these sings of leakage some do not.

Gas cap is also important and we should get a CEL if bad. But it may just be weak and not throw at DTC (CEL). Inspecting the seal of cap or just replacing it. But here I'd thing we get both CAT codes.

If using oil, between oil changes of 5K to 7k miles. This could be sign of oil getting into combustion camber. This can foul CAT, A/F and or O2. Oil loss, compression test and watch for smoke on start up are clues.

Basically we need to keep these VVT engine well tuned. Little things can add up and then we get issues.

All that said I feel many of the P0430 & P0420 when seen at near same time, are stemming from weak fuel pump. That engine ECU over compensates and we end up running rich fouling the CATS.
Then CATs run cooler and rich. CAT need to run hot to function properly and clean themselves. Then with other issue combine over time, cause CAT to clog.

Once all corrected up stream then we work on down stream.

I see bk 2 ST FT and LT FT are both positive. They are not out of line in fact look good. But I'd like to see bk 2 more like bk 1.
BK2 has higher .62V in O2. Question is why. This could be minor vacuum leak on bk2 and or exhaust leak. Could be wonky O2. Or a number of issue adding up.

What are CAT temps read from in TECK stream?
After warm up Run at idle, read CAT temps?
at 2K RPM record CAT temps at start of 2KRPM? and after two minutes held at 2K RPM?
Also use a IR temp gun and read temps on CATS. Google how to!

Also lets see some pictures of intake manifold.

If the code moves with swapping O2's and all else inline. New O2's should do the trick. So start there.

I would like to see compression test. Every mechanic I've every known has a compression gauge tool and can do the job.
 
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Timely. My rig just threw this code. Both sides - 0430 bank 2 x2 and 0420 bank 1.
Replaced 02s 3 yrs ago, but had a coolant leak last month and replaced the radiator.
Due to this thread, I just ordered a new gas cap and a couple O2s...
 
Interest CEL going out.

Do you have CAT Temps. After warm up Run at idle, and then at 2K RPM record CAT temps at start of 2KRPM and after two minutes held at 2K RPM..

Be interesting to see what happens when you swap O2s.

Have you ever had the intake gasket replaced?
Have you done a compression test?

so today i have done the 1- compression test = more than 100 psi on all cylinder (Plugs and coil boots are in good shape)
2- Swapped O2 sensors
3- checked for exhaust leak and there is none as per exhaust specialist and couple mechanics
4- gone to couple places to check coolant leak, there is none visible, though i havent missed any in the past 2 months (guess just in hot summer i lose few ounces).
5- mechanic checked intake manifold, he says no sigh of leak but i wouldn't know till it's opened
6- general checks for leaks hoses- none is found.
7- since i couldnt find gas cap yet, i cleaned my current one and lightly greased the seal.

so now i will see if the code comes back with p0430 or not.
btw, once done the compression test, i started the car, check engine was there, then after swapping O2 sensor, light has gone.

will post back any findings.
 
Compression: More than 100 PSI, is meaning less. 100 PSI is nowhere near minimum. Test is done engine hot, fuel pump shut down, throttle wide open, battery strong, >250 RPM. A reading from each cylinder needs reported here. We're looking for difference between cylinder to be in a range, also that all above a minimum. to low, even above minimum can give clues.

I've shown you pictures of clues to intake manifold leaks. Take pictures of the front and side of intake manifold. If oily crud climbing up side, it has a leak.

We want to know codes not just CEL on or off. Read the codes.
 
Compression: More than 100 PSI, is meaning less. 100 PSI is nowhere near minimum. Test is done engine hot, fuel pump shut down, throttle wide open, battery strong, >250 RPM. A reading from each cylinder needs reported here. We're looking for difference between cylinder to be in a range, also that all above a minimum. to low, even above minimum can give clues.

I've shown you pictures of clues to intake manifold leaks. Take pictures of the front and side of intake manifold. If oily crud climbing up side, it has a leak.

We want to know codes not just CEL on or off. Read the codes.
as far as engine hot, I know it took him good 30-40 to remove coils and sparks right after I parked the car inside the shop, so not sure if this is considered hot or cooled down.
before the mechanic started compression, I asked him what are we looking for here?, since I am not very familiar with it, he said " minimum 85 psi anything above 100 psi is good" that's done without disconnecting fuel pump nor throttle was wide open, maybe this how he does all Lexus I don't know but I can tell he knows what he is doing ( Lexus specialist shop). as far as compression, I know all cylinders have close numbers between 110-120psi and he said " all Cylinders are very good"

next: I will take pics of the intake manifold from all sides and measure heat for both Cats with 2 mins at 2000rpm with infrared thermometer.

"No Pending code yet."
 
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