mandyfig

Amazon with Prime:

Denso $54
NGK $59

mandyfig

I will get the DENSO. Thanks.

Bgw70

That is a good price Mandy, make sure the part numbers are the same, which they most likely will be.
Also, since you are a moderator, would that tech stream thread I started qualify for sticky status?
Or could it be combined with the TPMS sticky thread? Both of those subjects work together and we get so many questions that could be answered if people used the tech stream software. Thanks in advance!

Bgw70

I remember those threads and full of good info! I was really asking because I replaced bank two up and down sensors on my T/A a few months ago and just wondered if I should replace bank one also. I purchased all four but just being lazy on the bank one sensors. Guess I should do it now, they are more of a pain to replace.

Anyway, I replaced bank two because I was getting a P0430 and when I looked at the graph and voltage, I was NOT seeing the correct response from the downstream sensor. I decided to replace them. The code did stay away for some time but now it has come back. One thing that is common about both times has to do with me cleaning the fuel injectors.
Right after I ran Tecron the the tank I receive the P0430 code, then right after I did the direct injector cleaning it came back again. Coincidence, not sure?
Before I change the cat, I am going to make sure I have no exhaust leak on the passenger side because I know that can cause this code to show up! It happened on my sons truck.

Any thoughts Cole?

Mandy, sorry to hi-Jack your thread, I just it would be okay because you seem to have a plan...if you want I can delete my post.

Thank you both!

Coleroad

Downstream I'm only worried about if it has gotten bad enough to throw a code. Since all it's doing is monitoring the cat. Upstream, I figure one can't be to far behind the other. Plus keeping the air fuel ratio as close to stotiometric as possible. Will give me the best mpg, and be kind to my expensive cats.

nc356

iTrader: (1)

Coleroad seems to be one of the bright lights here, but I will beg to differ about replacing O2 sensors pre-emptively.
One of my 430's (LS) has 250,000 miles and still returns 26+ MPG on the highway, all on the original 4 O2 sensors.
However, my SC430, with only 90k miles is throwing the P0051; so I'm monitoring this thread closely.
In retrospect: I've put nearly a million miles on O2 sensor equipped cars; I have taken them all beyond 200k miles; this will be the first O2 sensor I've ever replaced.

O2 sensors are low cost parts and with high labor involved; even as a DIY item, I don't think it makes sense to put all that time into these sensors that don't seem to have a standard life cycle (like shocks as mentioned).

Looking forward to the progress of this thread; wish I had a lift at home!

Bgw70

Downstream O2 sensors are usually very easy to replace and sometimes the upstream sensors can be difficult.

If anyone wants the Lexus manual procedure, give me a shout and I will post it up.

Bgw70

Got ya and it makes sense. Time to climb under the old girl again to replace bank one sensors and to check for an exhaust leak on bank two. If not exhaust leak, then a new EXPENSIVE cat will be in my near future!

Coleroad

I've seen cars with 300,000 miles on the original o2's and not have a fault code. If you put one of those o2's against a new one on the oscilloscope. You will see the old one reacts slower than the new one. I know working in the field, it was change the failed part, not also be preemptive. On some cars like my BMW the up stream o2's are a knuckle busting bear. The extra labor would cost a lot. If I'm doing the job myself I'll take the extra time now to do both. The parts cost is relatively cheap. Knowing that they do get sluggish, and I don't want to feel like I'm doing the same job twice. Do I think if you don't change both your car is doomed? My no means do I think that. I guess I was saying if it were me and why. I haven't always done this, because I couldn't always afford to, not that I'm floating in it now either.

I think my day job has an effect on how I look at things too. I design quality control jigs for parts manufacturers. So like in the o2 sensor I know that the other one wouldn't pass quality control anymore. I realize my mind set may be different, and I realize I still have things to learn everyday. That's why I read every new post put up.

isfdude

iTrader: (11)

Make sure you use denso sensors as they are the OEM brand and almost all Lexus cars do that. The VSC and track light come on with the engine light and I don't know what traction control has do do with anything that triggers the engine light but I hit in to a curb because of loosing traction in snowy weather and my engine light was on for an open gas cap. I'm taking this to court with Lexus because there is no reason the system should do this at all.

nc356

iTrader: (1)

Coleroad,
Thanks for the thoughtful response.

So a question for all: does Techstream allow us to look at O2 sensor "response"?

Coleroad

I have heard that Toyota's and Lexus cars do not like Bosch o2 sensors. Not sure about other brands. I agree about using denso. And I know that's what you said you were going to pick up.

Coleroad

That's a good question for bgw's techstream thread. You should ask it there too.

mandyfig

I will check on making it a sticky. Have not done it before.

I ordered the O2 sensor based on your part number. This is the first time I ordered without checking the part number myself. Just give me an assurance that this was the right part number. I hope it right otherwise...LOL!

mandyfig

Confirmed! Thanks a lot. Upstream Right.