I unplugged the 02 sensor a few days ago, after driving it, I determined that there was pretty much no difference at all( Matter of fact, seemed like it drove slightly better without the 02 sensor). I left it unplugged for another two days and realized that it drove exactly the same, until the car started losing power at low speeds and the check engine light came on (Due to sensor being unplugged), so then I plugged it back in. I've been getting about 18 MPG mostly city,( +Even with it unplugged) which from what I understand isnt bad at all, none of these hesitations as long as it is plugged in and the idle is rough because of the mounts, but solid overall. Wanted to see what you thought, cause I dont have a lot of $ to play with, since I'm doing front+rear mounts this week. Thanks in advance.

 

Just thought id put i my $.02...my 02 was bad and i replaced it for 50 bucks at Nopi, and it has a little more power but it dosnt idle any better. You may have different results...thats just what happened to mine

 

you won't notice any difference in the idle usually.. it'll just be part-throttle driving that you'll notice the change.
I found out my problem with mine... turned out to be the sensor plug was full of water because the gasket fell out sometime when I installed my y pipe and had the sensor disconnected.
I doubt this is your case though..

if you check engine light came on after you disconnected the sensor, I'd say the sensor is still working somewhat.. try plugging it back in and see what happens.
my check engine light never came on after I disconnected mine on 2 seperate occasions.

 

92 SE..I unplugged mine for about an hour....noticed no change and the ECU lite did not come on either...I thought at least the check engine lite would have come on....but my car seems to run ok....however when I do the self ECU check, I get a "34" code which is the knock sensor....what symtoms would I notice if my knock sensor is bad....where is it on the VE motor, and what is the cost to replace??

 

It was unplugged for two days with no problems but when I was working and had the car running for pretty much 2.5 hours in a row is when this started happening. It was pretty bad, felt like I had 3 cylinders working at times. As soon as I unplugged it next morning, everything back to normal. One thing for sure, no difference at all in the driving conditions with or without the 02 sensor plugged in ( Until what I mentioned happened). Still thinking whether or not to get a new 02, I have a feeling it wont do anything in my case.