while under my car this past weekend, installing the replacement motor I noticed that the rear O2 sensor is messed up. the 3 wires that go into it are pulled out and not connected to the connector anymore. Does this really need to be there? The front sensor is fine but I am wondering if the car will act funny without this sensor hooked up.

Nick

 

so you think the engineers kinda just put it there for the hell of it?

 

ummmmm......no. but I was wondering if anyone had eliminated it or if it is not needed. Sorrry this is my first 240sx and was unsure of what everyone does with their cats and sensors.

 

if you want the car to run smoothly, plug it all back in. I have the same problem (O2 sensor not working) and my car runs like crap, throttle response is bad because the air fuel mixture isn't right, and I have idle problems too

 

Whats up kids long time no talk..
Been busy drifting to much.
Well anyway i sold my car..
Sorry no more KA! I loved it but...
Sponsored now!!!

I got a REAL SILIVA Ks....lol
jeff

 

Ok, I have been looking everywhere for this heated after cat O2 sensor and noone has it. every parts store I have called said they only have one for a manual trans car and mine is automatic. does the manual sensor work for the automatic too? please help

 

The rear 02 sensor is for OBD, it is basically there to check if the catalytic is working, or if it needs to be replaced. It doesn't affect the way the car runs or the fule mixture - but it does affect the MIL light.

 

Thanks Raine. I have found a couple for the car but all of the threads on the replacement sensors are to wide and wont go into the bung in the catpipe. I will keep looking.

Thanks again.

 

I had the same problem - junkyarding for some 02 sensor when I pulled the wires out during the clutch install... if you get OEM replacement, the lowest I've found was like $70 or something - all for an O2 sensor that basically doesn't do anything. Hell, the important O2 sensor (up front on the header) costs $15.

Lame. GL with your search.

 

thanks again.

 

ok.....I finally found one. the shipping is a little rediculous but whatever. if anyone else is looking for the same thing I found it at www.kbperformance.com. the sensor was $52 and ups ground shipping was $9. $61 bucks for the sensor and shipping. oh and its an NTK oem replacement.

Nick