Getting 2 Code From Cel

[flyboy56]

Here is some background, 2001 IS 300 Previous salvage

CEL has been on for long time, always ran fine. Since cold weather has set in runs like crap..I mean 10mph max until it gets good and warmed up. When cold CEL will flash along with trac off.

Bought a scan tool last night. came up with: random misfires on 3 cyl. the same p0161 code witch is the O2 sensor heater circuit malfunction, and the p1346 Intake CMP Sensor System Performance.

I cleared those codes and today i let it idle till warm..no CEL. took it down the street watching the I/M Readiness screen. Two codes popped up when the system had enough time to test Oxygen sensor heater monitor P0161 - O2 sensor heater circuit malfunction bank 2 sensor2 and P1346 again.

I have replaced all the plugs, blew out the MAF. What should be my next move? the bank 2 sensor 2(the one from the code) was acting a little funny too, i was watching the data and at idle it would hop around the ideal mv range, however when i would pump the throttle it would go to 0.000 and stay there for quite some time, where as the others would go right back to the mv readings.

Where/what is the O2 sensor heater circuit? how do I test to see if it is good/bad?

My wife is nagging about her car so any help would be great.

Thanks for your time.

John

[mdoan]

I got the same code p0161 on my 2002 is 300 ....

Dont know what to do yet......

Any ideas ????

Here is some background, 2001 IS 300 Previous salvage

CEL has been on for long time, always ran fine. Since cold weather has set in runs like crap..I mean 10mph max until it gets good and warmed up. When cold CEL will flash along with trac off.

Bought a scan tool last night. came up with: random misfires on 3 cyl. the same p0161 code witch is the O2 sensor heater circuit malfunction, and the p1346 Intake CMP Sensor System Performance.

I cleared those codes and today i let it idle till warm..no CEL. took it down the street watching the I/M Readiness screen. Two codes popped up when the system had enough time to test Oxygen sensor heater monitor P0161 - O2 sensor heater circuit malfunction bank 2 sensor2 and P1346 again.

I have replaced all the plugs, blew out the MAF. What should be my next move? the bank 2 sensor 2(the one from the code) was acting a little funny too, i was watching the data and at idle it would hop around the ideal mv range, however when i would pump the throttle it would go to 0.000 and stay there for quite some time, where as the others would go right back to the mv readings.

Where/what is the O2 sensor heater circuit? how do I test to see if it is good/bad?

My wife is nagging about her car so any help would be great.

Thanks for your time.

John

[flyboy56]

That code required me to change the bank 2 sensor 2. The sensor is on the passenger side about the middle of the door on the bottom. The sensor is easy to get to, the clip where it plugs into, is not. You have to take out the passenger seat, lift up the carpet and padding, and it is located near the center console. Lexus wanted $198 for their sensor which is a denso, i found a bosch for $161 and right on the sensor it says made by denso. You can buy the cheaper heated sensors and splice them in so that you don't have to do all that, but I wanted to eliminate as many possible problem areas as I could. I did have to change with the cars end of the wiring was mounted a little, just cut the tape, because the new O2 sensors harness was about 5 inches shorter.

I have not had that code or the misfires come up since. Now I am trying to figure out the intake camshaft postion sensor problem and that one requires some engine parts to be taken off.

Hope this helps.

John

[maswann]

I own a 2002 IS300 that is in almost new condition with 39,000 miles. I baby it that's for sure. Anyway, last Feb (06) Lexus replaced th B2S2 sensor under warranty. Here it is 12,500 gentle miles later and the same sensor is on again. This does pose a problem in my mind to think that I would have to pay to have this redone. Seems to me it was not done correctly last time or repalced with a faulty part. Seems like a Lexus issue to me!! I should not have to take my LEXUS (haha) to have the same sensor replaced every year. What do you think, am I being naive?

[gordonw]

It is true that any parts replaced by Lexus is normally cover under 1 year or 12,000 miles, which you have exceeded, but this situation is different because you're talking about your emission system. Emissions warranty are much longer than your basic warranty. You may want to check your warranty booklet. It will give the length of your emissions warranty and provide list of whats cover. Since your vehicle is about 5 years old with only 39k miles on it, you're probably still under the emissions warranty. My state goes by the California emission standard so our warranty is a little different (longer).

[maswann]

There is supposedly nothing wrong with my emissions it is the sensor light that keeps going out for some unknown reason. That part is no longer under warranty to my knowledge. Thanks for your reply, I appreciate it! Just hope they do the right thing and replace it or it's approx. $500 for me and if I have to replace it again next year then what?!

[gordonw]

I would check with dealer to make sure its out of warranty. Like I said, your emissions warranty is longer than your basic warranty. Ask them if your emission warranty is still in effect and if your B2S2 sensor would be covered. Another thing to consider is that the light is coming on for another reason. Are you getting the same code? It isn't clear in your earlier statement.

[maswann]

It is the exact same code as the one that they showed last year. The same sensor is bad again. I believe the initial warranty on that is 50,000 or 4 years. Last year when they replaced it the warranty was approx 2 weeks before expiring.

[smooth1]

There's a TSB about the heater sensor You can go here to see it Edmunds.com - Maintenance Popup

I'm pretty sure the dealership will just fix it.

[gordonw]

I'd still take it back to the dealer and see if they would still cover it. No harm in asking. Its possible the sensor has gone bad again, but I'd be suspicious as to why. My guess is thats theres something else wrong, that could be causing the sensor to fail. Worst case would be a bad cat. Do you have the code? I'll take look tomorrow.

[smartin143]

I have the same problem with my 2001 Lexus IS300. I've had it for four years now and the same B2S2 O2 sensor keeps going out. My husband replaced it the first time, but I had the dealership look at it this time and they quoted me over $400 to replace it. The service guy at the dealership told me the 2001 IS300's have this issue quite often. He said they changed the sensor configuration (or something like that) in the 2002 models so it's no longer a problem. But they see the 2001 models with the B2S2 problem all the time.

I realize this doesn't help you with your problem, but at least you know you're not alone.

Does anyone have a part number for this thing? I need to replace it so the darn check engine light will go off and I can pass my annual inspection (which expired in September). I've located a lot of places where I can order the sensor, but I have no idea what the part number is for this specific one.

Stacey

[smooth1]

I have the same problem with my 2001 Lexus IS300. I've had it for four years now and the same B2S2 O2 sensor keeps going out. My husband replaced it the first time, but I had the dealership look at it this time and they quoted me over $400 to replace it. The service guy at the dealership told me the 2001 IS300's have this issue quite often. He said they changed the sensor configuration (or something like that) in the 2002 models so it's no longer a problem. But they see the 2001 models with the B2S2 problem all the time.

I realize this doesn't help you with your problem, but at least you know you're not alone.

Does anyone have a part number for this thing? I need to replace it so the darn check engine light will go off and I can pass my annual inspection (which expired in September). I've located a lot of places where I can order the sensor, but I have no idea what the part number is for this specific one.

Stacey

If that's the case with this sensor, then I would just consider getting a dummy O2 sensor. basically it's a fake sensor that tells the ECU everything is good so you don't keep getting the cel, or light on the dash. And they are cheap. You can get them at any performance import parts place.

[lexusnexis]

I'll throw in my two cents worth on this topic. My friend has an '02 IS300 and it had the same cel code p0161 discussed here. She had somebody install a universal O2 sensor, part #USOS-4000. This thing is claimed to work in this car without a problem but that's not the case here. The code was reset but kept coming back. I did some research online including this forum and downloaded the service manual to help out. Since the manual specifically states that if the resistance reading on the heater circuit doesn't fall between 11-16 ohms at room temp, replace the sensor. I checked the front three sensors under the hood and they were in range. After finally figuring out where Bank 2 Sensor 2 connector was, under the seat, it read 4 ohms. This, remember, is the universal replacement. It was only a few months old. It had the gray,white,black,black wire combo. The instructions that came with this sensor were not very clear as to which wire went where. Although you can't mess up the heater wires. I looked around and found another sensor with OE wire color. Denso part #234-4209 from Auto Zone, not carried in stores. It was only $66 so that wasn't too bad. The resistance on this one checked out in range so that was a good sign. I installed it and reset the code and so far, 3 months later it hasn't come back on. Another Lexus forum posting does a good job of explaining and illustrating how to do the repair. O2 sensor replacement

BTW the Denso sensor is called a universal upper and lower sensor also.

Any other tidbits of info I came across were posted elsewhere online so no need to restate.

I just want people to know that this USOS-4000 sensor did not work for this car.

[izzy300]

EVERYBODY WITH O2 SENSOR ISSUES LISTEN!!

One drunken night I ran a whole can of seafoam through my 01 Lex IS300 intake, burning up two of my O2 sensors - B1S2 and B2S2.

I found an ebay store with them for $60 a piece - direct fit, no splicing required - ordered them and have thusfar replaced 1 of them, which took me from 2 CEL codes to 1.

Still trying to get the time to get that exhaust sensor harness, tho. GEEZ it seems it'll take a minute to do.

Anyway, just wanted to suggest ebay to those in need.

thanks to flyboy and all else who helped in this thread and good luck to all.

[smooth1]

EVERYBODY WITH O2 SENSOR ISSUES LISTEN!!

One drunken night I ran a whole can of seafoam through my 01 Lex IS300 intake, burning up two of my O2 sensors - B1S2 and B2S2.

I found an ebay store with them for $60 a piece - direct fit, no splicing required - ordered them and have thusfar replaced 1 of them, which took me from 2 CEL codes to 1.

Still trying to get the time to get that exhaust sensor harness, tho. GEEZ it seems it'll take a minute to do.

Anyway, just wanted to suggest ebay to those in need.

thanks to flyboy and all else who helped in this thread and good luck to all.

LOL!! I would have thought the bigger lesson is to not dump unkown crap into your car while in a drunken stupor! ;)

[bartkat]

:lol: