Thread: Removing the Rear O2 Sensor and Getting Rid of the CEL

I was just thinking that. Move the 2nd sensor right behind the 1st. I would assume it would work, it would be reading the same air.

Well behind the first would be kinda pointless, and one long wire lol, but I was thinking on the downpipe, towards the Cat there is a spot to put a wideband on. Maybe there?

Or maybe weld a spot on the Test Pipe

My reasoning for putting it closer to the first, is then the air will read more closely to the first. I dont know if the air will sniff different further back without a cat, but then again, Im not very educated in the workings of emission systems. I usually just rip them out.

Good point. I think the Rear O2 sniffer... err sensor , would have to read lower numbers because it is placed after the cat, so by the time the gasses get broken down/finished burning in the cat, then the O2 sensor picks it up. I would imagine it complaining when it's too close to the front O2 sensor...

Can anyone confirm or deny this?

Yeah, my brain isnt working today, work has me all scrambled. I just realized if the 2nd O2 sensor is closer, its going to make it think the cat is broken. At least I think.

Hehe it happens man

Yeah thats what I'm thinking....

In all honesty Vadim... I would just get an anti-fouler, screw it into the bung and screw in your second o2 sensor. The test pipe is going to make that CEL go nuts. This is what we do on the Evo's.

Cheers-

Hmmm, I never knew that. Here's something I found:

http://www.honda-tech.com/zerothread/2162522

Good find Swiss!! That is EXACTLY what I was talking about... Good man you are!

Cheers-

Yeah it looks like a cool trick. I guess it limits the amount of exhaust that makes it to the sensor... and a lower reading "after the cat," fools the ecu.