Bad oxygen sensor without cel?

[opent024]

since battling my stuttering/missing issues for about a month and replacing/cleaning everything (cap, rotor, plugs, wires, coil, fuel filter ICAV) I am wondering if my primary 02 sensor could be bad. Since I never see a check engine light (I know it works because it comes on when I unplug the ICAV) while I am driving, yet I still have issues, I am curious if its possible for my 02 sensor to be bad without any idiot lights.

[Acura2g]

Very possible to have a bad O2 sensor and no CEL. The problem with O2 sensors is that they will still function for way pass their recomended time. Most are good for 100k miles but you can go much further in most cases. What happens is the sensor will start giving you false readings, not at fault by the sensor but from the build up and backpressure from the cat. I would go ahead and replace it if you haven't already and make sure you don't get a Universal o2 sensor.

[food2000]

^ What's wrong with the universal o2 sensors (as far as i know, they just don't come with a plug)?

[opent024]

By the way, I have a 97 LS. I understand my primary sensor (before the cat) handles all my closed loop ecu air/fuel functions, so I suppose I can just leave the secondary alone for now since it doesn't have any effect on my air/fuel when at idle and such....

[coldfire]

Yeah the second is just for emissions. Doesn't actually serve a functional purpose.

[Acura2g]

Originally Posted by food2000

^ What's wrong with the universal o2 sensors (as far as i know, they just don't come with a plug)?

you have to cut and splice, the voltage that comes from a o2 sensor is .04 to .05v which is a small amount. Over time the water proofing devices will loose their protection along with dirt and road salt from the north can inhibit the connection causing that really low voltage to become even lower throwing off the readings that are being sent to your ECU.

[food2000]

Well... instead of splicing, you could soldier it? Maybe i'm missing the point here.

[Acura2g]

soldiering rusts and if it gets wet it can hinder the connection. when every you cut natural formed wire and tap into it via slipce or soldier you open the circuit to contamination.