what does this mean on the durametric software

[marksawtell]

I keep getting an error code P0154 - o2 sensor ahead of cat cylinder (4-6). Ive also had problems with the car revving at 1200 on idle, if I disconnect the MAF, it does go down to about 850. I have attached the readings of actual values on what i believe are the o2 sensors (being a 1999 uk 3.4 c2 convertiblle it only has a o2 sensor before the cat)

im an newbie mechanic so struggling with understanding certain areas. Can anyone make sense of this snapshot and tell me if im looking at the right thing and if it is showing the o2 sensor for cylynders 1-3 is showing faulty (this would be the o2 on the r.h.s as you stand behind the car looking at the back of the car...

thank you for any help!

[JFP in PA]

P0154 is the code for signal interruption on the indicated O2 sensor. While it could be a bad sensor, more often it is a wiring issue. You can electrically test the sensor to eliminate it as a candidate before you start tracing the wiring harness looking for damage or a loose connection.

[marksawtell]

Thanks JFP, whats your view on the graph , would you concurr be it wiring or the O2 sensor that it's the sensor with the flat lines ie which supplies the banks 1-3 ,which I'm assuming is the r.h..s sensory If you're behind the car looking at the back of the ( I'm assuming banks 1-3 are the lhs when in this position

[JFP in PA]

The code is definitely for bank 4-6 and ahead of the three way cat:

[marksawtell]

Thanks again jfp. it was the o2 sensor in the end..... got a zig zaggy line on both now on the graph ;-)

[JFP in PA]

Glad it worked out; most people do not realize the O2 lines on the display are supposed to move back and forth.

[logray]

The read on wiki about lamda is pretty useful...