Getting code P0430 in my 2007 LX470 (1 Viewer)

[xzzz]

The CEL and the VSC OFF/TRAC lights turned on in my 2007 LX470 so I plugged it in and saw that it's throwing a code P0430. Where should I start with this? I can post the data from Techstream, does any of the data seem out of line? Should I just clear it and see if it comes on again? I recently had the spark plugs replaced and the throttle body and the MAF cleaned if that's relevant.

Data from Techstream:

 

[LI FJ40]

02 sensor

 

[1NTRANSIT]

Correct ^^

Bank 2 is the passenger's side. TS should be able to specify which of the two B2 sensors has faulted. Sensor 1 = front, Sensor 2 = rear. Amazon has good prices on Denso replacements.

 

[atnolan94]

Correct ^^

Bank 2 is the passenger's side. TS should be able to specify which of the two B2 sensors has faulted. Sensor 1 = front, Sensor 2 = rear. Amazon has good prices on Denso replacements.

I have this code and need to pass inspection this month. Anyone have a good writeup on O2 sensor replacement? My searches have been fruitless and admittedly of all the things I can do on cars I have never replaced an O2 sensor.

 

[1NTRANSIT]

I've luckily only had to replace a single rear sensor, 10 min job. 02 sensor socket is a must. https://www.amazon.com/gp/product/B00390BS7C/ref=oh_aui_detailpage_o09_s00?ie=UTF8&psc=1

 

[atnolan94]

I've luckily only had to replace a single rear sensor, 10 min job. 02 sensor socket is a must. https://www.amazon.com/gp/product/B00390BS7C/ref=oh_aui_detailpage_o09_s00?ie=UTF8&psc=1

Cool/ I've heard all 4 are the same p/n is this true?

 

[nissanh]

For a 2000 LC, rear O2 sensor is attached with two 12 mm nuts. Check before buying tools. Try to stay with OEM sensor. Or try denso made in Japan. I am not kidding, denso made here in the US is not as good as denso coming from Japan.
Amayama.com has goodprices on oem parts but takes 2 to 3 weeks to get here.

 

[TokenSki3r]

Just did the same

Cool/ I've heard all 4 are the same p/n is this true?

Part numbers are different for front and rear, and also different depending on year of vehicle. If you only have a P0420 or P0430 code, its most likely just the rear sensor. I just replaced both rear sensors on my 03 after the dealer told me I for sure needed new cats. Three months and a few thousand miles later, no codes.

Super quick and easy job. No special tool needed for the rear. Make sure the car is cold. I shot the old bolts with a little WD40 a few hours before I did the job and everything came off easily. Bought Denso sensors on amazon for around $50 each.

 

[badlander]

02 sensor

Correct ^^

Bank 2 is the passenger's side. TS should be able to specify which of the two B2 sensors has faulted. Sensor 1 = front, Sensor 2 = rear. Amazon has good prices on Denso replacements.

I have two vehicles with this code. Please explain where techstream shows the fault as being the O2 sensor and not the catalytic converter. I'm not seeing it in the data shown......
Thanks

 

[nissanh]

The cat is made out of precious metals, Pd and Rh. These are catalysts and not a reactant so cannot get consumed in a reaction. It is always O2 sensor that goes bad. I too had p0430 code and a scan at the zone told me I need a new CAT. I didn't believe it. Replaced the rear O2 sensor and no code came for past 100 miles.

 

[Irshfshr]

I had the same code 7 or so months ago with my '06 LC. There's a good amount of discussion on here about P0430, most of which, as I recall from my research indicated that the fix was most often found by replacing the downstream sensor. That's the one in the CAT, not the exhaust manifold. I also recall much of the discussion being from those with Techstream ( which I do not have) being unable to isolate the rear O2 sensor as being the source of the problem. The consensus proved true for my LC as well and replacing the rear sensor got rid of the code and check engine light.

As far as a write-up, I don't recall if there are any, but if you get under your LC and find the CAT, the rear O2 sensor is the thing that looks like a spark plug with a short wire harness coming out of it. Once you identify it, removal will be pretty self-explanatory though the little plastic plug/clip might be frustrating as I think the plastic tab that must be depressed in order to unplug is on the back side of the plug and hidden from view. Replacement of the front sensor is slightly trickier because it's in a tight space. Do yourself a favor and get an O2 sensor replacement kit from your local auto parts store. It's an extension that will attach to the end of your 3/8 ratchet and it has an open end that will let you slip the fitting over the wire harness. My local Autozone had such a kit that they rented for free, with a $30 deposit.

Incidentally, as I had first purchased the upstream sensor by mistake, I figured what the hell and I ended up changing the remaining three sensors, after having fixed the P0430 issue. With 4 brand new, Denso, sensors I found my gas mileage improved significantly from a gas guzzling 9-10 city and 13-14 hwy. to an Earth-saving 12-13 city and 15-17 highway.

 

[white_lx]

The later models LX/LC use an Air-Fuel sensor before the catalytic converter (S1), followed by a conventional oxygen sensor after the catalytic converter (S2). They are completely different sensors. Techstream lists them as 'AFS' for the A/F sensor signal and '02S' for the oxygen sensors.

To verify if the actual sensor is the problem one can swap L and R sensors. Alternatively, sensor operation can be verified by driving the mixture lean (pull a vacuum hose) and rich (propane or brake cleaner into air inlet) and monitoring the S2 signals (rich: > 0.45V, lean <0.45V). Techstream also has an option to decrease or increase injector volumes to achieve the same.

If you don't want to go to the trouble of doing the testing, the downstream oxygen sensor is a pretty good guess. Before buying a new sensor, I would start by verifying that there is no leak in the exhaust system where air can enter. It can throw the same code.

This should fix the check engine light. The VSC light is from C1201 (wheel speed sensor error). The O2 sensor replacement will not fix that.

But what about all those Bxxxx codes? Do you have an airbag light? I would be a lot more concerned about those!

 

[xzzz]

The VSC light is from C1201 (wheel speed sensor error). The O2 sensor replacement will not fix that.

But what about all those Bxxxx codes? Do you have an airbag light? I would be a lot more concerned about those!

It was my understanding that the VSC Lights come on in conjunction with several (most?) CELs as a side effect, so I'm not too worried about those.

As far as the airbag codes, I don't have an airbag light, and TechStream shows those as historical codes, so I'll take a look at those if they come up again. Right now the passenger detection works (when a passenger sits, the light comes on), so I'm not sure why those are there.

I'll try replacing the O2 sensor and see where that gets me.

 

[tacoduck]

I had the same code. replaced the downstream sensor on bank 2, and no change. Turns out it was the upstream sensor on bank 2 that was bad. I have a sharp mechanic who diagnosed it for me and changed the upstream sensor, and it fixed the code.

 

[badlander]

Guys, thanks for clarifying the rear o2 sensor diagnosis. Maybe I'll take a chance and invest in a new one for our VW.

 

[buddysharp]

P0340 code showed up a couple of times after long highway trips only. Replaced both upstream sensors with Denso OEMs. Code popped again. Replaced one downstream so far with Denso OEM (on Bank 2 where the code showed up) and will replace the other shortly. Hoping for no more codes. 2004 100 series just turned 200K. Easy job on the rear sensor btw; fronts were a biatch due to clearance and not having trump hands.

 

[OEMGUY0720]

Hello gents joining this thread. Same thing happened to me this morning, CEL came up as well as VSC TRAC and VSC OFF.
Ran techstream and got this:

About 2 months ago I replaced my upstream (the one on the exhaust manifold) O2 sensors -both banks driver side and passenger side with Toyota OEMs I got from the dealership.

P0430 is somehow referring to the O2 sensors on the catalytic converters itself from what I read.

@buddysharp how's your truck now, did the CEL or P0430 came up again after replacing both bank1 and bank2 O2 sensors on the catalytic converters?

Thanks gents.

 

[looking4lc]

i have had that code replaced both O2 sensors and it was gone. 2 years later it poped same code again!!!
is it possible to be replaced again?

Notes: i have used Marvel Mystery oil on tank 50 Miles later, it disappeared for awhile. what does that mean?

 

[hydronos]

Can someone provide me the part numbers for the O2 sensors for p0430 - 07 LX470

 

[DJCloz]

Any updates on the part number?