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electrical problem O2 sensor

kscontourkid

Veteran CEG'er
Joined
Nov 4, 2004
Messages
941
Location
Overland Park, KS
the upstream bank 2 O2 sensor is not reading at all on my car. the sensor is brand new. the old one did the same thing which is why i changed it to begin with. i have only a P0430 code to go off of... ive looked at the wiring diagram and it looks as though there is nothing between the pcm and the sensor on the control circuit. what might be causing this phenomenon? has anyone had this happen before?
 
The PCM cannot possibly post a P0430 code if the upstream sensor is faulty and is not reading at all.

You have reached an improbable conclusion.

Steve
 
that is what all data i have collected is showing. my sct scanner throws an error code because the computer apparently doesnt even know its there??? it wont show up at all in a datalog
 
i gots no cats :shrug: i have had the lowers shut off and my upstream shows 0.000 in a datastream. the other 3 O2 sensors read fine and are alternating what looks to be normally (to my untrained eye). i originally got a P0155 upstream heated O2 sensor circuit fault (one of the circuit fault codes for the bank to upstream sensor) and i changed the sensor hoping that would solve the problem and the sensor was old as well.

before i start disconnecting and probing wires i wanted to see if anyone had had this problem before.

im just confused as to why it only throws a P0430 and doesnt throw anything else :shrug:

guess i have to start probing :( i hope i didnt break anything.
 
Update

Update

just thought id read my dtcs on my car and see if i had any codes set. i now have a P0153. anyone had this one before? and what did you do?
 
if you don't search for more ....



[FONT=arial,verdana,helvetica,sans-serif]P0153[/FONT][FONT=arial,verdana,helvetica,sans-serif]Upstream Heated Oxygen Sensor circuit Slow Response - Bank No. 2. [/FONT]

replace the O2 sensor ....
 
i gots no cats :shrug: i have had the lowers shut off and my upstream shows 0.000 in a datastream. the other 3 O2 sensors read fine and are alternating what looks to be normally (to my untrained eye). i originally got a P0155 upstream heated O2 sensor circuit fault (one of the circuit fault codes for the bank to upstream sensor) and i changed the sensor hoping that would solve the problem and the sensor was old as well.

before i start disconnecting and probing wires i wanted to see if anyone had had this problem before.

im just confused as to why it only throws a P0430 and doesnt throw anything else :shrug:

guess i have to start probing :( i hope i didnt break anything.

how did you have the Lowers turned off? via a tune, i presume since you have a 3L? with the lower O2s turned off you wont get a precat code and, IIRC, you shouldnt be able to read any data for them.
 
when you are data logging what are you using? I ask because a few times recently when I have been datalogging with my xcal2 and Live link the O2 parameters I select do not display correctly.
 
i am using an Xcal 3 then uploading to my desktop. i dont have a laptop :(

ok time for a list and the reason i am confused. ive done all my homework without pulling the whole harness out and ripping it apart.

1. installed 3L with no catalytic converters
2. got tune from Joey (nautilus performance) X-cal 3
3. got DTC P0430 and P0155. figured ok that was an original sensor on the car. time to change it. (that is upstream bank 2)
4. changing the sensor got rid of the P0155 but the P0430 is still there.
5. took a data stream with an Actron scanner from Advance Auto (where i work) and found the BRAND NEW upstream bank 2 sensor was reading 0.000 and the other 3 were reading .9 or something of the sort and were all fluctuating together.
6. put my new intake on and cleared the codes. now i only have a P0153.
7. i traced the wires on the car from the O2 sensor to the main harness and could find no breaks cracking or wear of any kind without taking it apart and examining it inch by inch.


i dont mean to sound harsh. i want to make sure we all know that i have done my homework but im having a little trouble trying to figure out why i cant seem to find X.

i am very confused and on the verge of pulling the harness. problem is this car is my daily driver. any help would be wonderful. the sad part is it is probably the simplest thing imaginable.

thank you for any input

i just want it to quit throwing random a$$ codes.
 
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