Yet Another O2 sensor question

[whitebois]

So I have a 91 manual. I sometimes get an o2 sensor fault code under hard acceleration - when the sensor goes into open loop mode- at around 5500 rpm. This is around the same RPM the VTEC starts to become active. I have noticed when it is cool out, this happens more frequently. Also I have seen discussion on this site regarding "mixing up " the front and rear sensors. I don't understand why the front and rear sensors would not be identical to each other except for the length of the wiring harness. My car has a Dali Chip in it as well. My thought is to just replace the sensors- they are the original ones and are reasonably cheap. Any thoughts?
Thanks

 

[pingu81]

Are you running any aftermarket headers, test pipes, or exhaust? Maybe a 02 simulators would eliminate the CEL. It worked for me.

 

[Cozmo]

The sensors are the same. They're talking about having them plugged into the wrong side of the engine.

 

[whitebois]

yes, exactly my point- if they are the same it would not matter where you put them in other than the length of the wiring. Not sure what you are getting at. Also, the 91 only has sensors upstream of the cats.
Thanks

 

[Cozmo]

You don't understand.. it doesn't matter which sensor you put into which hole in the headers. What matters is whether you plug the correct sensor into the right connector on the engine. I think you'd know it if they were backwards.

How many miles are on your sensors? What about spark plugs?

 

[angus]

You don't understand.. it doesn't matter which sensor you put into which hole in the headers. What matters is whether you plug the correct sensor into the right connector on the engine. I think you'd know if it they were backwards.

How many miles are on your sensors? What about spark plugs?

Wow Brandon, you are getting smarter...

 

[Cozmo]

Wow Brandon, you are getting smarter...

hah. I was never stupid, just inexperienced in certain areas.:biggrin:

 

[whitebois]

Ah, OK now I get what you are saying. Car has 50k miles on it- I assume they are the original sensors. Probably a quick change- out is warranted-these things are not expensive.
Plugs only have 15,000 miles on them.
Thanks