Friday, June 3, 2011

Is it ok if my oxygen sensors are reversed on my car?

I just had someone change my exhaust manifold, calaytic converter, and 02 sensors on my 1998 Honda Civic. I just found out that they might have been put in reversed (top on bottom and bottom on top). Is this ok to have or should I have it changed back?|||The same sensor is used in both positions -- no problem with that is possible.





The wiring won%26#039;t even begin to reach from the upper to the one downstream of the catalytic converter if you try to swap the connectors on the two sensors -- no problem with that is possible.





Unless someone has been fooling around with the wiring (literally swapping pins in a connector or doing some serious cut and splice work in your harness), it%26#039;s not possible to %26quot;reverse%26quot; them.





IF, on the other hand, someone HAS been fiddling around with the wiring such that these two have been reversed, then yes, it%26#039;s a real problem as it will be seriously fouling up the computer%26#039;s understanding of your pre-converter mixture at the %26quot;upper%26quot; sensor. The %26quot;upper%26quot; pre-converter one is important to how well your engine runs. The post-converter (%26quot;lower%26quot;) one just provides an indication of how well your emissions controls are operating.


.|||I%26#039;m not sure what you mean by top and bottom O2 sensors, but if one is upstream and one is downstream, they must be put back in the correct location or it can kind of play tricks on your vehicle%26#039;s computer. Each measures the same thing, but the levels of what they measure are different; the computer knows which is upstream and which is downstream. (Note: upstream= before catalytic convertor, downstream= after convertor) Now, if the O2 sensors are both upstream or both downstream, they should still be in the right place, but if they aren%26#039;t you may never know any difference. Hope this helps.|||That wont make a difference for the sensors as top O2 sensor or bottom O2 sensor...... an oxygen sensor is an oxygen sensor..... it will be ok, dont worry about it.