Hey everyone, im new here, and i was browsing around and didnt see what i needed to know. So heres my question, I just got my lexus back from the body shop(1999 LS400) and my check engine light came on. So i stopped into my local autozone to have them scan the codes, and it came back with the O2 sensor after the cat on the drivers side. The guy at autozone said i should replace them in pairs, is that right? And my main question is, i can get at the O2 sensor no problem, but it appears that the harness runs inside the car through a rubber boot. Looks like a PITA to me to take the interior apart. Can anyone point me in the right direction here? BTW the car has 80k on the clock. Thanks in advance.

Nate

 

what code did youhave, he should have told you....

 

They did tell me, but i didnt write it down. The guy at autozone did look the code up for me, and i remember looking at the screen, and it listed: air leak, or O2 sensor, bank 1. If it would help i can take it back down to autozone and get the actual code from them.

 

if it's p0430 or similar (catalytic efficiency below threshold) it's more likely to just be a dead exhaust gasket that's causing a leak.

 

I totally agree.

This happened on my truck. We have an O2 sensor, then two cats back to back, then a second o2 sensor. I had a leak in the gasket between the two cats that was causing the insufficient cat code. Replaced the gasket and all has been good for over 2 years.

 

Sorry the response took me so long, i was out of town. I went this morning and the code that is read is P0136. Any input would be appreciated.

 

PD am getting this code P0430 , so does replacing the gasket after cat on passenger side will solve this?
Can i have the part number please?

 

http://www.obd-codes.com/p0136

Since you got the trouble code after
Don't buy any parts, first start with your DIY free inspections.

So am sure that the best thing should be done is to start with cleaning any corrosion on the sensor + inspect the sensor harness which could be unplugged by the service guys who were cleaning your car + inspect the sensor relay then delete the code & check if it comes back or no ? because maybe it could be a Faulty code.

By the way Bank 1, Sensor 2 is the sensor which comes in driver side after cat. The harness is under the driver seat. slide your driver seat all over to forward.

 

Thanks qewani1, i looked under the drivers seat, and didnt see anything that would lead me to the O2 sensor, im about to look again, but i will try the cleaning 1st and see if that takes care of things. I dont have a scanner at the moment, on the lexus is it fine to remove battery cables and run the lights for 10 minutes? I had an e320 benz that if the battery died you would have to take it to the stealer for a 1000 dollar reprogram of everything. Like my windows wouldnt even roll down, nothing in the car worked.

 

most of time Circuit means a problem with the wiring.
Check attached file.
With the diagnosis tool does the O2 sensor show any readings?

 

This guy has a nice video of where the passenger side o2 sensor is and how to remove carpet.

1999 passenger oxygen sensor location

 

Thanks, that's very helpfull, I'll be changing all four O2 sensors on my 98' LS400 soon.