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computer keeps reading o2 sensor. swapped out twice. rough idle getting worst. help.

Old Jan 25, 2022 | 12:08 AM
  #46  
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good luck!
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Old Jan 25, 2022 | 10:29 AM
  #47  
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tested out the fuel injectors. getting about 11.3-11.6 ohms

have to order another cooling system pressure test. the one i got off amazon said it for the jeep but didn’t.



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Old Jan 25, 2022 | 11:19 AM
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Was the resistance the same in all 6 of them? Did you clean them? Did you hear a click when you connected a 9-volt battery to push the cleaner through?
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Old Jan 25, 2022 | 12:25 PM
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Originally Posted by Very Red XJ
Was the resistance the same in all 6 of them? Did you clean them? Did you hear a click when you connected a 9-volt battery to push the cleaner through?

resistance was consistent throughout. i’m only working with a multimeter at the moment so i wasn’t able to connect a 9 volt battery.

i will run to the hardware store and see if they have something to connect them

in the meantime. i tested the the o2 sensor connectors again and am getting a 3.8-4.0 reading when testing on the following setting while the car engine is on but both o2 sensors disconnected



the gal lending a helping hand ofcourse

please note that the reading i’m getting is coming from connectors 3-4. when testing 1-2 my multimeter reads 0.0


are these readings good?

freeze frame mentioned open loop and a diagnostic tech told me to continue with testing the o2 sensors although CEL disappeared

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Old Jan 25, 2022 | 12:36 PM
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You can get short leads with alligator clips at each end at an auto parts store
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Old Jan 25, 2022 | 01:07 PM
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also, i want to add that i’ve left the o2 sensors disconnected and have been running the car now for almost 30 minutes and still no rough idle

a little shake every now and then but nothing consistent enough to call a rough idle patch. hm.

Last edited by fr3dbilli3; Jan 25, 2022 at 01:13 PM.
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Old Jan 25, 2022 | 02:35 PM
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man man man, i think i've just figured it out, or so i freaking hope.

below theres a photo of 2 o2 sensors, the black on is the ntk i am trying to install in my car, the other, the one the car already had one (dont even know what brand).

i start with the front and like a dummy i screw in the o2 sensor before realizing that the conncetor doesnt match, so i go to the back with the 2nd o2 sensor and its a match, whats going on here. turns out that, both o2 sensor on this vehicle as i got it are the exact same sensor. the front connector on this jeep wants to match with the grey connector and the back with the black connector. the previous mechanic sanded down one of the notches on the back connector so that the grey sensor can fit. can this be what was causing the issue? and its weird becuase when i look on rockauto i only see 1 type of ntk sensor for my car.


the grey connectors tunnels are more spaced then black ngk
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Old Jan 25, 2022 | 02:45 PM
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Couldn't hurt do it right and my XJ has an O2 on each side of the cat - the front one has a heater element. That last parts replacer shouldn't be called a mechanic
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Old Jan 25, 2022 | 03:10 PM
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Originally Posted by fr3dbilli3
... can this be what was causing the issue?
Do the wires (white, black, grey) match up OEM vs Rube?
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Old Jan 25, 2022 | 03:17 PM
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That rock auto listing made my head hurt when I looked at it for my 2000
if you look at this
https://ngk.mypartfinder.com/
You will see that the connectors for front and rear sensors are different-as you have already figured out.

How much different the 2 sensors would work as far as looking at the o2 in the exhaust I don't know, probably not much,

but if the OBDII fault system is looking for a heater on the front sensor and there isn't one it's going to set a code.
chrysler would not have gone to the trouble/expense to have 2 different connector key configurations if they could be interchanged.
Keep in mind the last person who worked on that thing was responsible for those spark plugs... And the cut vacuum line.

Just saying..
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Old Jan 25, 2022 | 03:19 PM
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Originally Posted by Dave51
Do the wires (white, black, grey) match up OEM vs Rube?


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Old Jan 25, 2022 | 03:34 PM
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Originally Posted by exasemech
chrysler would not have gone to the trouble/expense to have 2 different connector key configurations if they could be interchanged.
Yeah kinda like printer cartridges.
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Old Jan 25, 2022 | 03:47 PM
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Originally Posted by exasemech
That rock auto listing made my head hurt when I looked at it for my 2000
if you look at this
https://ngk.mypartfinder.com/
You will see that the connectors for front and rear sensors are different-as you have already figured out.

How much different the 2 sensors would work as far as looking at the o2 in the exhaust I don't know, probably not much,

but if the OBDII fault system is looking for a heater on the front sensor and there isn't one it's going to set a code.
chrysler would not have gone to the trouble/expense to have 2 different connector key configurations if they could be interchanged.
Keep in mind the last person who worked on that thing was responsible for those spark plugs... And the cut vacuum line.

Just saying..
thanks for the input but i must say im completely stuck after swapping only the one that was incorrect (back sensor) and now seeing a check engine light with p0132 code.

(my car only has 2 sensors)

i posted the test results for multimeter voltage from connector earlier today, should i be seeing some numbers when i connect the multimeter to the heater circuits?

let me know where i should go from here. starting to lose momentum but i'm holding strong.

still have to test injectors.


might get PO132 tattooed on my chest after this mission



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Old Jan 25, 2022 | 03:51 PM
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If it's from an OBDII anything it has a heater. And speaking of wasted expense whoever made the Rube isn't gonna put 4 holes and 2 wires connected to nothing.

Meanwhile


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Old Jan 25, 2022 | 03:54 PM
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And



So I really can't see any reason why it wouldn't work fine.

BTW are you running in "open loop" now? Can you generate O2 waveforms with your software?
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