porn-adkt

iTrader: (37)

Aftermarket usually dies after 1 to 2 years.. the guts is cheap ceramic

aneidiaz

Thank you my friend. Ppl always wanna take the cheap way out. I don't. I know I'm problem free around my exhaust area for MANY years to come.

aneidiaz

Here's before and after pics of my cats. The difference was surely felt.







I just left the car back in the shop again. For hopefully the last time with this o2 sensor issue. Had code PO125 come up after everything. Apparently B1 S1 was defective. It was completely dead. So I gotta new one from Advance Auto, Denso brand. Let's see if that fixes that darn CEL light!

penny1

I am new to this forum but I am having a similar issue. I have a 2004 GS 430 and the dealer said I need Bank 1 Sensor 1 and a Cat. I took it to Firestone to have the sensor replaced. They replaced both sensors (Pre-Cat). Still have Check Engine Light and VSC on. I can't get it inspected. Took it back to Firestone they replaced the sensor but same code. (B1S1...no reading from sensor) Then they tested the wiring harness and only one wire out of the four is reading voltage. They finally said it has to do something with the wiring but the Denso sensor is not the problem. I no longer have a Cat code but still Bank 1 Sensor 1. Any help????https://www.clublexus.com/forums/images/smilies/pat.gif

aneidiaz

Dam bro what a coincidence. I JUST HAD THE EXACT SAME PROBLEM. I had both my cats, all gaskets, and all 4 o2 sensors replaced last week. Upon receiving car back, a lil while later the CEL turned back on. PO125 code and all my guy at the shop noticed was that B1 S1 was not reading at all.. long story short, I bought another sensor thinking it was a defective sensor when it really wasn't.. luckily my guy is very inclined and he gets the job done. Apparently he said the wiring harness connecting to the o2 sensor B1 S1 was completely age corroded. He said 2 wires were completely split. He said that he took it and rewired the damaged ones back. Visually inspected every other component of the harness and reinstalled it back. Got the car back yesterday. CEL off..... and I hope it stays that way!! So far so good.

I see your in the same predicament as me. Just don't panic, stay positive bro. Take the harness to someone or a reputable place YOU KNOW is great at electrical work. If you can't do so yourself. If all 4 sensors are new, most likely it's the wiring harness. But in your case, you said you know it's the harness. Just those wires repaired and reinforced. Once everything is plugged in, everything should go away. Unless you have air leaks..... I suggest replacing ALL pre and post cat gaskets. Also have visual inspection of exhaust to see if there's anymore air leaks. Replace all gaskets if needed. Www.sewellparts.com has it all for cheaper. Sign up with your CL account to get discounts bro! Good luck!!!