P2626 - I've run out of ideas

[C-los]

Originally Posted by bmwlover0725

Edit: 8 monitors did set and all was well, but now the CEL is on again...

Uh Oh, whatcha got?

[bmwlover0725]

Originally Posted by C-los

Uh Oh, whatcha got?

Same thing

[dpaul]

Originally Posted by bmwlover0725

Edit: 8 monitors did set and all was well, but now the CEL is on again...

So what code is associated with the CEL? Still P2626?

[bmwlover0725]

Originally Posted by dpaul

So what code is associated with the CEL? Still P2626?

Yes. Monitors set after clearing it when replacing spark plugs. Light came back with P2626 after a couple hundred miles. Could this be the fault of a leaking injector? The starting is better now, but still a slightly hard start after sitting overnight. I just wonder about injectors since it’s one of the highest mileage E9X M3’s on the road.

[dpaul]

Originally Posted by C-los

D-paul, no where in my post did i sugget they were dead. i asked about his x pipe, and i said he could replace them (o2's) again if he wanted to, to double check.

Either way, doesn't matter now.

I apologize for any misunderstanding.

I meant that the OP said they were dead or injured (Post #13). What ever happens in Bank 1, when P2626 is set, that sensor is injured. Why? because the OP says that if he swapped that sensor from Bank 1 into Bank 2, the code follows to Bank 2. If the sensor was OK, there would not be a code in Bank 2.

Perhaps I misunderstood the OP. If so, again I apologize and this whole topic is moot. But if whatever happens in Bank 1 does injure pre-cat sensors, what could be the cause? I read your posts as suggesting a possible DME problem. If that were so, to explain what the OP has said about how and when the codes occur, the DME would have to be injuring the sensor. If it were just a DME problem, then all those sensors the OP replaced should actually still be good.

That said, maybe there is some unusual DME failure mode in which the sensor is injured. It is clear (in the N54 world) that DME failures can destroy injectors and coils. But those are high current circuits and devices while the sensors are not. That is why I asked if you knew of any relevant cases.

I hope this logic makes sense to you. Since the OP is still reporting the same problem, I think it actually does still matter. It seems worth trying to think more about the cause.

[dpaul]

Originally Posted by bmwlover0725

Yes. Monitors set after clearing it when replacing spark plugs. Light came back with P2626 after a couple hundred miles. Could this be the fault of a leaking injector? The starting is better now, but still a slightly hard start after sitting overnight. I just wonder about injectors since it’s one of the highest mileage E9X M3’s on the road.

Could be but leaky injectors are usually not that subtle. And one argument against that is your trims which are normal. How's your gas mileage; notice any changes in that since this started happening?

Also, what do you mean by hard starting, exactly?

[bmwlover0725]

Originally Posted by dpaul

Could be but leaky injectors are usually not that subtle. And one argument against that is your trims which are normal. How's your gas mileage; notice any changes in that since this started happening?

Also, what do you mean by hard starting, exactly?

Good lord... I'm almost embarrassed and ashamed to say what this turned out to be. I've always known bank 1 as driver side even on this car for the past several years. The only time I ever replaced something that was wrong on another bank was a throttle actuator, but I did them both at once so I wouldn't have noticed.

That being said, I just replaced the bank 1 sensor on the passenger side. The driver side is already new of course since I thought it was bank 1 so at the end of the day - I've ended up with two new O2 sensors and a new set of plugs that is vastly better than the old ones. Also as a heads up, DO NOT use Ruthenium plugs. They are not compatible with this engine at all and there are other threads on it. Of course I found those threads AFTER I started getting multiple misfires. Just figured I'd throw it in as a side note.

Stay tuned for when I'm wrong again the light comes back!

[dpaul]

Originally Posted by bmwlover0725

Good lord... I'm almost embarrassed and ashamed to say what this turned out to be. I've always known bank 1 as driver side even on this car for the past several years. The only time I ever replaced something that was wrong on another bank was a throttle actuator, but I did them both at once so I wouldn't have noticed.

That being said, I just replaced the bank 1 sensor on the passenger side. The driver side is already new of course since I thought it was bank 1 so at the end of the day - I've ended up with two new O2 sensors and a new set of plugs that is vastly better than the old ones. Also as a heads up, DO NOT use Ruthenium plugs. They are not compatible with this engine at all and there are other threads on it. Of course I found those threads AFTER I started getting multiple misfires. Just figured I'd throw it in as a side note.

Stay tuned for when I'm wrong again the light comes back!

I'm glad you feel you've figured it out and I really hope this is the end of your worries. However, I'm as confused as fuck by what you just said. AND to be honest, dismayed by this late revelation that you've been experiencing 'misfires', a word you've never used in this thread before. Did you not think this could be relevant to the O2 codes? In the future including all information about codes, driveability issues and modifications to the drivetrain upfront will make it more likely you'll receive useful feedback.

[bmwlover0725]

Originally Posted by dpaul

I'm glad you feel you've figured it out and I really hope this is the end of your worries. However, I'm as confused as fuck by what you just said. AND to be honest, dismayed by this late revelation that you've been experiencing 'misfires', a word you've never used in this thread before. Did you not think this could be relevant to the O2 codes? In the future including all information about codes, driveability issues and modifications to the drivetrain upfront will make it more likely you'll receive useful feedback.

I should have included that, but I figured it was a totally separate issue because I looked into it and found that it can cause the misfiring problem so I just swapped back to another plug. I do see where you’re going with that though and I should have said something. Either way, this was simply a bank 1/2 misunderstanding. I’ve never seen a car that had them reversed like this. Maybe I’ve been living under a rock.

[dpaul]

Originally Posted by bmwlover0725

I should have included that, but I figured it was a totally separate issue because I looked into it and found that it can cause the misfiring problem so I just swapped back to another plug. I do see where you’re going with that though and I should have said something. Either way, this was simply a bank 1/2 misunderstanding. I’ve never seen a car that had them reversed like this. Maybe I’ve been living under a rock.

Yes, I think most manufacturers put Bank 1 on the drivers side while BMW and Ford have number 1 cylinder (and hence Bank 1) on the passenger side. Plus BMW/Ford number the cylinders 1-4 for Bank 1 and 5-8 for Bank 2 while GM has the numbering hop from side to side. Trying to remember firing order is hopeless. I always have to look things up because I'm never sure.

Fingers crossed for no more CELs.

[bmwlover0725]

Originally Posted by dpaul

Yes, I think most manufacturers put Bank 1 on the drivers side while BMW and Ford have number 1 cylinder (and hence Bank 1) on the passenger side. Plus BMW/Ford number the cylinders 1-4 for Bank 1 and 5-8 for Bank 2 while GM has the numbering hop from side to side. Trying to remember firing order is hopeless. I always have to look things up because I'm never sure.

Fingers crossed for no more CELs.

Update: monitors set with both sensors being new. Looks like I’m good to go again! Glad I replaced plugs anyway.

[C-los]

No Biggie DPaul, forums and text sometimes jumbles what we mean and can come across, or be interpreted incorrecty.

As for Bank numerations.

On V and H style engines,
Bank 1 is "normally" (edited due to correction, there are weirdo manufacturers that go against the norm) on the Right side, when looking from the back of the engine . I've yet to see Bank 1 be the left. Not to be confused with Audi/VW, it's on the drivers side only because their engines are flipped around (i.e. nose of crank goes to flywheel, belts are driven by the rear of the crank.

In regards to inline engines,
4cyl are always just bank 1,
most 6 cylinders split the engine in half, front 3 is bank 1, back 3 is bank 2.

[dpaul]

Originally Posted by C-los

No Biggie DPaul, forums and text sometimes jumbles what we mean and can come across, or be interpreted incorrecty.

As for Bank numerations.

On V and H style engines,
Bank 1 is ALWAYS on the Right side, when looking from the back of the engine

I assure you this is not the case. When the motor has a conventional longitudinal orientation GM V8 (and V6) motors (and Chrysler I believe) have cylinder 1 and hence Bank 1 on the Left side (driver's side), when looking from the back of the engine.

The opposite of BMW, Ford and some others.

[C-los]

Well, i stand to be corrected (and i've adjusted my previous post, i should've known better than to use the word... always...). I've never worked on GM products, so i appreciate the lesson.

funny, i think i've worked on everything but them. hahaha.



All still good OP?