O2 no activity! (No NYS inspection too) F!

Rovergroup

Member
Mar 23, 2014
14
1
Rochester
Welp, could use an idea gents or other, 3 sets of new Bosch and can’t wipe no activity banks 1/2. Guessing O2s are good...after so many freshies. I’m stuck. :(
 

rovercanus

Well-known member
Apr 24, 2004
9,643
244
I'm assuming this is a D2 from your avatar? I would say ecm or harness. You can also check fuse 2 under the hood or connector c0635 going into the ecm to make sure it isn't loose.
RAVE is your friend.
 

discostew

Well-known member
Sep 14, 2010
7,706
1,015
Northern Illinois
I think maybe you don't have a ground on the red and black wires at all the sensors. They all end up at the same connector on the ECM. I've fixed a couple trucks by just cutting them out of the connector at the ECM and splicing them together and grounding them to the bracket that holds the modules behind the glovebox.

I think this happens because of the way BMW stops monitoring stuff like O2s. They break the ground and stop running the circuit all together. I figured out the monitoring side of the ECM thats watching o2 activity doesn't give a shit where the ground comes from.
 

Rovergroup

Member
Mar 23, 2014
14
1
Rochester
I think maybe you don't have a ground on the red and black wires at all the sensors. They all end up at the same connector on the ECM. I've fixed a couple trucks by just cutting them out of the connector at the ECM and splicing them together and grounding them to the bracket that holds the modules behind the glovebox.

I think this happens because of the way BMW stops monitoring stuff like O2s. They break the ground and stop running the circuit all together. I figured out the monitoring side of the ECM thats watching o2 activity doesn't give a shit where the ground comes from.
Okay good idea thanks. I did all 4 O2, then truck was in garage for new gaskets about 3 wks. Took it out, tossed rack and fun accessories back on and got about 135mi before codes. Before that....I replaced engine bay fuse block entirely since during head gasket, I put in new radiator and during burping completely flooded the block, yes had the cover off and I don’t know why. So the truck died while doing 40mph in the city and jumped a snow bank to avoid the left turning car. Yippee. Turns out coolant was sloshing around and the r9 I think (engine) sizzled. Interesting diagnosing until I remembered the great coolant flood. Anyway, tracing rave last night found the 14 plug connect next to SAI is O2 power! And prayed to Rover gods it was hammered by the flood. It seems okay, doused in cleaner. Air drying. We’ll see. Splicing the ground is a great idea and because I accidentally used logic and reason, thought a short or open code would be seen not no activity. Especially on both upstream. Sooo perhaps bad ground is the answer! Out of nowhere is so fun. We know how it goes though, I bang my head on the wall because is feels good when I stop.
 

Rovergroup

Member
Mar 23, 2014
14
1
Rochester
Okay good idea thanks. I did all 4 O2, then truck was in garage for new gaskets about 3 wks. Took it out, tossed rack and fun accessories back on and got about 135mi before codes. Before that....I replaced engine bay fuse block entirely since during head gasket, I put in new radiator and during burping completely flooded the block, yes had the cover off and I don’t know why. So the truck died while doing 40mph in the city and jumped a snow bank to avoid the left turning car. Yippee. Turns out coolant was sloshing around and the r9 I think (engine) sizzled. Interesting diagnosing until I remembered the great coolant flood. Anyway, tracing rave last night found the 14 plug connect next to SAI is O2 power! And prayed to Rover gods it was hammered by the flood. It seems okay, doused in cleaner. Air drying. We’ll see. Splicing the ground is a great idea and because I accidentally used logic and reason, thought a short or open code would be seen not no activity. Especially on both upstream. Sooo perhaps bad ground is the answer! Out of nowhere is so fun. We know how it goes though, I bang my head on the wall because is feels good when I stop.
Not the connector near SAI, will try to set monitors again before splicing to Ecm I guess. I feel like I’m missing something, maybe not. Did do valve for exhaust at sai since that popped up after head gasket during O2 tracking. Like, vacuum? Maf? Bang!
 

Rovergroup

Member
Mar 23, 2014
14
1
Rochester
Not the connector near SAI, will try to set monitors again before splicing to Ecm I guess. I feel like I’m missing something, maybe not. Did do valve for exhaust at sai since that popped up after head gasket during O2 tracking. Like, vacuum? Maf? Bang!
(Solenoid) for sai valve
 

Rovergroup

Member
Mar 23, 2014
14
1
Rochester
Do you have a scanner that can monitor the o2 sensor activity? Cause your going to need that.
I have a “LR” one I got from an eBay builder. It’s not strong but can go into ABS etc which is nice. The language is iffy for O2 data. Will get it in a verus hopefully today to see actual data. Heater is the issue so it can make its own voltage. Idfk
 

discostew

Well-known member
Sep 14, 2010
7,706
1,015
Northern Illinois
If you pull up the o2 voltages they should be moving around a lot. If they sit at a steady 500 mv then they are inactive. All the resetting adaptions or cleaning shit won't help. If all 4 are fixed at a reference voltage I would suspect you lost the ground I'm talking about.
Backprobe whatever sensor is easiest to get to on the red/black wire. Then ground the thing with a jumper wire. If the voltage starts to fluctuate that's your problem.
If you just keep doing all this other shit before you do this simple test your just wasting time. Yours and ours
 

discostew

Well-known member
Sep 14, 2010
7,706
1,015
Northern Illinois
I have a “LR” one I got from an eBay builder. It’s not strong but can go into ABS etc which is nice. The language is iffy for O2 data. Will get it in a verus hopefully today to see actual data. Heater is the issue so it can make its own voltage. Idfk
Heater is not the issue. You said it's activity. The heater will run on warm up to get into closed loop faster. The other half of the sensor is your issue. All 4 sensors have a red/black wire at them. All of them need a ground at the ECM. Any time I've seen no activity at all the sensors it's been that.
 
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Rovergroup

Member
Mar 23, 2014
14
1
Rochester
If you pull up the o2 voltages they should be moving around a lot. If they sit at a steady 500 mv then they are inactive. All the resetting adaptions or cleaning shit won't help. If all 4 are fixed at a reference voltage I would suspect you lost the ground I'm talking about.
Backprobe whatever sensor is easiest to get to on the red/black wire. Then ground the thing with a jumper wire. If the voltage starts to fluctuate that's your problem.
If you just keep doing all this other shit before you do this simple test your just wasting time. Yours and ours
Roger that- so wiring checked out thankfully, was concerned I wrecked something during head gasket and really started over thinking the situation. The no heater and no activity was not actually from wiring problems but the sensors themselves and I mistakenly expected the Bosch replacements (3 times) to be an okay oem replacement. Which it was not. The stubby blade vent style apparently does not cooperate with this truck. The walkers/denso did and are longer and filled with holes. So with voltage swings now reading and fuel trim next was monitors. Was able to trick sai into test conditions with 3 house fans on radiator and wife’s hair dryer at intake but kept throwing cel. So still not getting enough o2 swing reading to pass. Got evap and just killed ignition repeatedly when sai pump tried to kick on which allowed inspection sticker!!!! Now can f around with sai over time. Has vacuum, took filter out of pump thinking better air flow, clamped and sealed pipes for leaks, swapped solenoid and thinking the bank one can isn’t allowing enough flow. Unsure.
 

Rovergroup

Member
Mar 23, 2014
14
1
Rochester
Heater is not the issue. You said it's activity. The heater will run on warm up to get into closed loop faster. The other half of the sensor is your issue. All 4 sensors have a red/black wire at them. All of them need a ground at the ECM. Any time I've seen no activity at all the sensors it's been that.
I was chasing heater thinking the piezo could only generate voltage based on heater working and since wasn’t open circuit or short, if heater wasn’t working neither could voltage which would equal no activity.