Hi, my 90 si has hesitation/stutering at constant speed until the check engine comes on, then all is fine. CEL code is 1 (oxygen sensor). There does not seem to be anything wrong with the wiring.

I am looking through ebay and found the ngk/ntk brand and bosch brand, and I remember seeing comments about certain o2 sensors that made the car run like crap even if the part was brand new so I would like to get peoples opinion on this,

Also, can my bad o2 sensor cause a fluctuating idle? idle goes up to 2000rpms for maybe half a second then drops back down and up again. I have cleaned the IACV thoroughly (wasn't very dirty) and I have bled the coolant, was just wondering if a bad o2 could cause this.

thanks

 

There is also Denso, which I know is usually good quality, 10$ more than the ntk.

 

when in doubt run ngk. denso is, if im not mistaken, a sister company of ngk

 

bosch is one of the best oem parts manufacturer......all widebands use one of the o2 sensors from bosch

 

I had the same problem with my iacv and cleaned it and looked new but just wouldnt work.tried my friends iacv from his car and workes beautifull.my guess is u should just replace it like i did

 

Denso, NGK, Bosch in that order. I hate putting Bosch on a customers car because they just don't seem to hold up as well.

 

bosch o2 sensors suck.......wideband o2 is another story.....get the denso or ngk

 

got the denso!! thanks!

 

i too have fluctuating idle, did you fix yours ?