O2 Help

[20Liberty03]

Hello, looking for some help, I keep getting codes 0551, 0141 and I am expecting 0161. I have flushed the power steering system to try and get rid of 0551, I replaced both downstream O2 sensors with NTK (NGK) brand sensors to get rid of the 0141 and 0161 codes to no avail. Any suggestions as to where I should go from here would be greatly appreciated. My next step is to take it to the dealer. TIA

 

[JeepinJarhead03]

bad fluid wont cause an p0551
a faulty sensor, damaged wiring or bad plug connection will

as for the O2's trace the wiring, starting from the power steering pump area in a 3 foot section from the harness down, there may be a pinch or physical damage causing all 3 MILs (O2's and PS)

 

[20Liberty03]

Thanks, will have a look. Of course that is the hard side to work on, lol

 

[20Liberty03]

0551 has been there all along, 0141 and 0161 only started after another code, 0158,prompted me to change the bank 2 sensor 2 but I put a Bosch sensor, that's when the 0141 and 0161 started

 

[Myke]

0551 has been there all along, 0141 and 0161 only started after another code, 0158,prompted me to change the bank 2 sensor 2 but I put a Bosch sensor, that's when the 0141 and 0161 started

Don't know how true it is but others have said Bosch O2 sensors don't play well with NTK/NGK O2 sensors. If no one else pops up and says I'm wrong I'd try using only NTK/NGK sensors.

While you're in there make sure the o2 wiring isn't coming in contact with anything that would cause interference as another user stated his wire was coming in contact with his trans or drive shaft and throwing odd readings.

 

[LibertyTC]

Bosch oxygen sensors don't work well at all in the jeep, kinda crappy really oop:
Use NTK only and the Jeep will be happy.:gr_grin:

 

[20Liberty03]

I did replace both O2 sensors with NTK sensors and now 0161 has gone away but 0551 and 0141 are still there. I did not notice any pinches in the harnes, will double check that the wire is not touching anything. Thanks for the info

 

[tjkj2002]

I did replace both O2 sensors with NTK sensors and now 0161 has gone away but 0551 and 0141 are still there. I did not notice any pinches in the harnes, will double check that the wire is not touching anything. Thanks for the info

P0141 is for B1S2 heater circuit,you either got unlucky and got a bad O2 sensor out of the box(it happens) or you have a wiring issue.Depending on the year of your KJ and exhaust configuration a shorted downstream O2 wire is very possible and not uncommon.

 

[J33Pfan]

P0141 is for B1S2 heater circuit,you either got unlucky and got a bad O2 sensor out of the box(it happens) or you have a wiring issue.Depending on the year of your KJ and exhaust configuration a shorted downstream O2 wire is very possible and not uncommon.

is there a way to check the 02 connector with a volt meter before you replace the 02 sensor?

 

[tjkj2002]

is there a way to check the 02 connector with a volt meter before you replace the 02 sensor?

Yes there is.You'll need the wiring schematic and find the 2 heater wires(most are both white wires) and with the connector unplugged measure the resistance of the heater,most say 10-18 ohms for a good heater element.

 

[Blackhawk77]

Sorry to drag up an old thread but I have a p0141 and p0551, and p0158. I replaced both downstream sensors with new ntks and the codes didn't go away for the O2s. Wondering what fixed it for you, thinking wiring at the moment which scares me.

 

[Billwill]

Sorry to drag up an old thread but I have a p0141 and p0551, and p0158. I replaced both downstream sensors with new ntks and the codes didn't go away for the O2s. Wondering what fixed it for you, thinking wiring at the moment which scares me.

Some codes only get cleared after a few start/stop runs but if you have physically cleared the codes and they still come back then you have no choice but to get into the wiring diagrams.

What year KJ do you have?

Download the year of your KJ here... 2004 is only year not included so in this case I would suggest 2003 but wiring colors will be different.

Section 8W has the wiring diagrams while the 2006 documentation has a DTC index at the end of the Index page that gives some good advice on what to check for the codes.

You will need a cheap digital Multi meter to measure continuity from point to point and for leakage to chassis/engine. With all ends of the wires disconnected....including splices....there should be no leakage at all to ground! If there is no continuity from point to point check the various connectors in line with the wires as shown in the diagrams.

If there is leakage to ground it means a wire is chaffing to chassis or to another wire within the harness somewhere which can be difficult to access.
So in this case you will need to cut off all ends of that circuit...including splices so that the circuit is hanging in mid air. Then replace that wiring circuit with new wire taking the shortest point-to-point route.

I had to do this 9 times due to a front collision damaging the main harness up front.:emotions34:

Jeep KJ Service Manuals: Index of /manuals/Jeep/KJ