Can a bad o2 sensor cause the engine to idle rough and die on a 2004 RX8

You don't clean O2 sensors , if bad you replace them . An only if there is a DTC - diagnostic trouble code or you check out O2 sensor performance with testing , using scan tool , lab scope or multimeter . A rough idle is usaully caused by a vacuum leak , a engine misfire , IAC - idle air control air passages clogged . There are videos on youtube on how to test to find rough running problems .

replace the o2 sensor(s)

That's Random or multiple missfire code. Have you checked for proper fuel pressure? Improper fuel pressure will trigger this code if it's too low, thus causing a lean mixture in multiple cylinders.

P0171 is a lean Oxygen Sensor code. It is trying to tell you that your engine is running lean...not getting enough fuel, or getting too much air. That will cause the poor running and dying. This is most likely caused by a bad vacuum leak. The O2 heater code is probably caused by a failed O2 sensor heater. Sometimes it is caused by an open or short in the O2 sensor circuits, but most of the time it is the sensor itself.

Hello jack_mathews,

Yes, an o2 sensor tells the computer if the exhaust gases or too rich or too lean. If the computer is told the by the o2 sensor that it's too lean the computer will increase the amount of fuel delivered to the engine thereby reducing your fuel economy, and if the o2 sensor is stuck on lean the computer will continue the increased fuel delivery.

The increased fuel can foul the plugs and cause a rough idle.

Regards,
netvan

okay, the o2 code can cause problems, theres a problem with one of the o2 sensors, theres 2 or 4 sensors,the repair was not done right or theres another bad o2 sensor, next thing i would check is the idle air control motor,this sounds like it sticks at time or just stops working,start with these things first,

I have a 2005 f150,with a 4.6 and it idles rough and when you turn on the ac it wants to die. Checked the codes and there are no codes.Any suggestions?

it's not likely a bad o2 sensor would cause it to run rough, but the catylitic converter, which is what the o2 sensor reads the flow of, would cause the car to idle and run rough.If you take it to an auto parts store to have a diagnostic test ran on it( most major parts stores will do this for free), thecodes it gets would help pin point it alot better.

your hetred o2 sensor is also what some manufacturers call a fuel/ air metering sensor, primarily because this is exactly what it does. with a faulty 02 sensor the computer doesn't know if the engine is running rich or lean, there for causing a rough idle, repair this as quickly as possible because damage can be done to the catalytic convertors. this can cost upwards of 1000 bucks to replace depending which engine. no matter which engine you have, replace both o2 sensors in the bank that is causing the problems, this is more important with the gm line than most but holds true to all vehicles

a car that idles rough and clears up is the sure sign of an o2 sensor shorted this may not give a code if the short in the sensor is bad the computer will eliminate its input to protect itself