O2 sensors not reading...
#1
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A friend and I replaced my Oil Pan and Timing cover gasket due to a serious oil leak and in order to remove the oil pan we had to unbolt headers and unbolt motor mount and raise motor..
Well everything went back together smoothly but none of the four O2 sensors are reading... Car runs ok, just like its running in closed loop ALL THE TIME..
Threw a P0154 code(O2 sensor Circuit No Activity Detected Bank 2 Sensor 1)
Also threw a P0100(Mass or Volume Air Flow Circuit Malfuncton)
Is there a Fuse I should check?
-Kris
Well everything went back together smoothly but none of the four O2 sensors are reading... Car runs ok, just like its running in closed loop ALL THE TIME..
Threw a P0154 code(O2 sensor Circuit No Activity Detected Bank 2 Sensor 1)
Also threw a P0100(Mass or Volume Air Flow Circuit Malfuncton)
Is there a Fuse I should check?
-Kris
#6
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as odd as it is i had the P0154 before and seafoamed the car and the code went away. i think that might have been a coincidence though.
also with the headers, check your extensions, maybe a wire popped off of the connector between the factory harness and the extension.
also with the headers, check your extensions, maybe a wire popped off of the connector between the factory harness and the extension.
#7
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I'd check fuses first, they are on the front drivers side corner of the engine bay.
I a problem with my O2's a while back and found blown fuses. Turned out one of the bundles of wire from the PCM running down the passengers side wheel well had a broken loom and laid against my LT headers and shorted an O2 wire, it was in a spot that was not easily seen.
I a problem with my O2's a while back and found blown fuses. Turned out one of the bundles of wire from the PCM running down the passengers side wheel well had a broken loom and laid against my LT headers and shorted an O2 wire, it was in a spot that was not easily seen.
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#9
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The down stream(sensor 2) are for emissions, and depending if you have them disabled for an ORY they may have a constant reading. Mine are disabled due to the ORY and the reading never changes.
The up stream sensors (sensor 1) are what your worried about, their reading should be bouncing high to low few times per second. If the fuses are good start checking the wires, look for something that is unhooked, pinched, broken, ect. Its not a fun job.
The up stream sensors (sensor 1) are what your worried about, their reading should be bouncing high to low few times per second. If the fuses are good start checking the wires, look for something that is unhooked, pinched, broken, ect. Its not a fun job.
#10
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The down stream(sensor 2) are for emissions, and depending if you have them disabled for an ORY they may have a constant reading. Mine are disabled due to the ORY and the reading never changes.
The up stream sensors (sensor 1) are what your worried about, their reading should be bouncing high to low few times per second. If the fuses are good start checking the wires, look for something that is unhooked, pinched, broken, ect. Its not a fun job.
The up stream sensors (sensor 1) are what your worried about, their reading should be bouncing high to low few times per second. If the fuses are good start checking the wires, look for something that is unhooked, pinched, broken, ect. Its not a fun job.
#11
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Is bank 1 sensor 1 working?
If so do a quick test and swap the O2 sensors with each other from bank to bank, if the problem follows the sensor you have a bad sensor. Another tip is to mark the sensors before you go swapping from side to side, you don't want to find you have a dead sensor and confuse the two.
If one of the sensors is bad it could have gotten hit, bumped, dirty or damaged when you were working on the car.
If so do a quick test and swap the O2 sensors with each other from bank to bank, if the problem follows the sensor you have a bad sensor. Another tip is to mark the sensors before you go swapping from side to side, you don't want to find you have a dead sensor and confuse the two.
If one of the sensors is bad it could have gotten hit, bumped, dirty or damaged when you were working on the car.
#12
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Ok.. on my scanner its says: P0154/P0100
0.0 on BOTH front O2 sensors (and both rears, but they're tuned out)
Bank 2 sensor 1 is reading 444 millivolts constantly
Bank 1 sensor 1 is reading normaly...
I've been reading and it seems to throw the P0100 code after a header install..
Could my bank 2/1 be reading weird bc I burned a wire and would that cause my MAF to read funny???
Car was fine with NO CODES before the work we did...
BTW.. it says "NO ACTIVITY" not "MALFUNCTION"
0.0 on BOTH front O2 sensors (and both rears, but they're tuned out)
Bank 2 sensor 1 is reading 444 millivolts constantly
Bank 1 sensor 1 is reading normaly...
I've been reading and it seems to throw the P0100 code after a header install..
Could my bank 2/1 be reading weird bc I burned a wire and would that cause my MAF to read funny???
Car was fine with NO CODES before the work we did...
BTW.. it says "NO ACTIVITY" not "MALFUNCTION"
#13
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When it reads that dummy value, 450 usually...it just means its not receiving any signal from that 02 sensor. If everything is hooked and no burnt wires...just replace it. You might have knock the sensor around or got oil on it...they aren't that much to replace ~50 to 60.
#14
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When it reads that dummy value, 450 usually...it just means its not receiving any signal from that 02 sensor. If everything is hooked and no burnt wires...just replace it. You might have knock the sensor around or got oil on it...they aren't that much to replace ~50 to 60.
#15
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Hey guys i need to bring this post back up and hijack it....sorry. i had my check engine light come on yesterday. Scanned it, scanners states both passanger and driver side upstream o2 sensors no activity. Any ideas, I could understand one not active but both? I checked fuse box under the hood labeled engine (20 amp fuse) and the fuse is not broken.