O2 sensor failing? Increased emissions, Engine malfunction

[strokemycocktus]

I've been getting random check engine lights with increased emissions message that would go away randomly. Stock x-pipe, stock ECU. Recently I got a engine malfunction message with limp mode after changing the wheels at a shop (car was lifted a bit). Went away after ignition off and back on.
About 2 weeks after that I got the emissions warning again that did not go away. On saturday I took it for some spirited driving and restarted the engine after I cam back. Suddenly the car was idling very roughly, shaking, and I got engine malfunction reduced power error. Did not go away after restarting the engine immediately, but was gone when I started it the next day. The tank was only about 1/8 full.
The car runs completely fine, just idles a bit low (about 500 rpm) and vibrates slightly (but no audible misfire).

I've had some battery issues (increased discharge) and noticed that the IBS connector cable (the small one) was slightly damaged - replaced it. Car has just under 70k km. Spark plugs replaced about 15k km ago.

Here are the DME codes:

CDC0	DME: Throttle actuator CAN message, bank 2
2B57	DME: Motor emergency programm activated
2B21	DME: Throttle-valve actuator pre-drive check, bank 1
278F	BSD, message; intelligent battery sensor (IBS): Missing
2791	DME: IBS general
2728	DME: Oxygen sensor, coast-mode diagnosis before cat., bank 1
2750	DME: Oxygen sensor fault pump current cable before catalytic converter, bank 1
2B35	DME: Misfire with cutoff, cyl. 1
2B36	DME: Misfire with cutoff, cyl. 2
2B37	DME: Misfire with cutoff, cyl. 3
2B38	DME: Misfire with cutoff, cyl. 4
2B41	DME: Misfire with cutout, several cylinders
2796	DME: Motor emergency programm activated
27C1	DME: Info: Tank empty on fault entry
2B42	DME: Misfire impairing exhaust emission, cyl. 1
2B43	DME: Misfire impairing exhaust emission, cyl. 2
2B44	DME: Misfire impairing exhaust emission, cyl. 3
2B45	DME: Misfire impairing exhaust emission, cyl. 4
2B4E	DME: Misfire impairing exhaust emission, several cylinders
27B1	DME: Secondary air system flow rate, bank 2

I believe I need to replace the negative battery cable with IBS, pre cat O2 sensor bank 1 and what else? Are my throttle actuators on the way out or not? I can't see the "typical" 2B25 / 2B26 codes so maybe they're not dead yet...

Seems there is a problem with the "bank 1" (passenger side?) of the engine leading to misfire and increased emissions and therefore O2 sensor errors... But also bank 2 secondary air system? What could cause all this?

[strokemycocktus]

After clearing all the codes I've driven a bit and got another limp mode - happened after I left the car for about 30 min after a short drive and started it up again. Restarting the engine again made everything back to normal. Car runs totally fine except low and slightly hesitant idle.
I got only 2 codes this time:
CDC0 DME: Throttle actuator CAN message, bank 2
2B57 DME: Motor emergency programm activated

Details say the CDC0 error was recorded at just 124 rpm. Engine temp 65 C.
So, Throttle actuators or maybe throttle position sensor?

[ItsGary]

Originally Posted by strokemycocktus

After clearing all the codes I've driven a bit and got another limp mode - happened after I left the car for about 30 min after a short drive and started it up again. Restarting the engine again made everything back to normal. Car runs totally fine except low and slightly hesitant idle.
I got only 2 codes this time:
CDC0 DME: Throttle actuator CAN message, bank 2
2B57 DME: Motor emergency programm activated

Details say the CDC0 error was recorded at just 124 rpm. Engine temp 65 C.
So, Throttle actuators or maybe throttle position sensor?

Throttle Actuator on the Driver Side.

[strokemycocktus]

Originally Posted by ItsGary

Throttle Actuator on the Driver Side.

I'm afraid that's the sad truth. But what about all the bank 1 mess? O2 sensor and missfire errors?

[ItsGary]

Originally Posted by strokemycocktus

I'm afraid that's the sad truth. But what about all the bank 1 mess? O2 sensor and missfire errors?

If the codes didn't come back after you cleared them, I wouldn't worry about it. Just focus on the persistent codes first.

[strokemycocktus]

I have ran a test though ISTA and both banks turned out all OK. But bank 1 made a slightly different sound than bank 2 lol.
When I start the engine the revs stay most of the time at about 500 rpm, but then slowly rise to 800-900 (just like I would gently touch the throttle). It stays there for a while and when I actually touch the throttle the revs raise a bit and then drop back to 500. Then in happens over again. No faults are recorded.

Any other reason for these problems? I know throttle actuators are the most common, but I'm not sure if these symptoms are what most people describe and the codes are different too.

[strokemycocktus]

So far the limp mode didn't go back. Car runs fine just with lower idle, but from what I read this can be also battery related (I have solved my IBS problems recently). Car idles stable, just lower - at about 550 rpm.

I have pulled codes today and now have these two:
5E19 DSC:Engine Managment: interface
2750 DME: Oxygen sensor fault pump current cable before catalytic converter, bank 1

I have also done the O2 test via ISTA and these are the results.

[tmak90]

Could attempt to take the pre cat O2 and swap it to the other side to see if code follows. If code follows then could be a faulty O2 sensor.

[strokemycocktus]

That's basically my plan for now, just need to find some time for it

[M3 Number 86]

can you run live data? I've dealt with this for the past few months lol

you want to look at fuel trims + precat o2 sensor voltage. no need to swap sensors back and forth. the fuel trims (LT+ST) should max at around 3%. if they're fine it'll be close to 0%. based on the readings it could be a dead sensor, a slight leak (new gasket), etc.

is your idle value based on what you think by looking at the tach? Mine looks like 550ish but live values show fluctuations between 650-700.

[strokemycocktus]

Originally Posted by M3 Number 86

can you run live data? I've dealt with this for the past few months lol

you want to look at fuel trims + precat o2 sensor voltage. no need to swap sensors back and forth. the fuel trims (LT+ST) should max at around 3%. if they're fine it'll be close to 0%. based on the readings it could be a dead sensor, a slight leak (new gasket), etc.

is your idle value based on what you think by looking at the tach? Mine looks like 550ish but live values show fluctuations between 650-700.

Thanks for the suggestion, I'd definitely like to try it. Can you recommend a program that can be used for live data? I have Inpa and ISTA, can I find such feature there somewhere?

[M3 Number 86]

Originally Posted by strokemycocktus

Thanks for the suggestion, I'd definitely like to try it. Can you recommend a program that can be used for live data? I have Inpa and ISTA, can I find such feature there somewhere?

Can you get to this page? I use something else but I found this on YouTube.

[M3 Number 86]

This one is better. I think inpa starts at 4 mins.

[M3 Number 86]

Do you have a low battery? A new one may help. Happened to me as well. There's a thread in here about it.

[z3papa]

I can tell you the "Bad Emissions" error code in the M3 is got to be one of the most frustrating generic codes I've ever gotten from any car. I chased this last year with the "assistance" of a dealer to be fuel pressure, then throttle actuators, then 02 sensor, at which time I replaced also the spark plugs. $3500 later, I thought the problem was resolved until this winter. Not I get the codes when I drop down to 1/3 of a tank, and it goes away when I fill up. Can't tell if the new issue is as simple as a bad gas tank cover, but I also think it can be something connected to the thermostat as it only is a cold weather issue. Before anyone asks, yes, I can pull all codes but the codes only tell you a part of the problem. Right now, the CEL is off.

[///Monty]

So just FYI (don't want to add to extra/misinformation), my experience with this:

Throttle Body Actuator threw similar faults, limp mode, etc.

What happens?
The TBA over a period of time will begin to wear on the gear inside. When opened up, you may notice that some of the teeth are grinded into a more rounded shape instead of sharp points that can be grabbed well. This slippage from the rounded edges is what throws the codes and causes limp mode.

You have two options:
1) Send your TBA off for repair or order the gear upgrades yourself and install. There is a shop that machines a "to-spec" alloy version, which replaces the trashy plastic OEM gear. This essentially removes future faults almost entirely. I want to say last I looked, this route was under $100 if you do it yourself. The kit included gears for TBA1 and 2.

2) Buy some new TBA and install. They are $500-$1000 each, depending on where you can source them.

I actually went the 2nd option initially because I was unaware of the indy shop that was making the replacement kits, but as soon as I installed the TBA's, all issues immediately went away.

As far as your O2 problems, i think some other people here listed better information than I could think up. I am not a car guru, I just try to pool as much knowledge and associate it best I can with my individual problems. 02 Sensors are a pain in the ass because, in my experience again, it can be a LOT of different issues. 02 sensor could be bad, or low voltage across sensor, or fuel/air ratio for emissions is off, or sensor has been installed wrong (actually suprisingly common ).

Good luck.

[strokemycocktus]

Thanks everyone for the replies. Unfortunately I wasn't able to run real time diagnosis through inpa, it seems I have some files missing - when I choose MSS60 it throws an error that some data is missing and I only have the basic functions available. In ISTA I have only found a diagnostic routine that I have ran (results above).
However, to me it all seems to be a 'central' electric problem:
1. The limp mode goes on ONLY immediately after a startup when the engine is slightly warm (I drive for 5 mins, engine off, back on - limp mode/ engine is at operating temperature, the car is left with engine off for 30 min - limp mode). Never after a cold start in the morning and never when the engine is fully warmed up.
Engine off and back on gets rid of the limp mode, without even a check engine light.
2. I get a mix of errors (todays readout attached) - O2 sensor, IBS, throttle actuator - but not the typical one (troubleshooting broshure attached).
3. I constantly get water in my battery compartment. All taillight gaskets were replaced, the trunk vent as well. It seems to be leaking somewhere from the side (hence the vent replacement), but I have ran out of ideas. The 'shelf' where all the modules are placed is dry.

I may have a weak battery. I need to check the voltages, charge it overnight and then check again. I'll post the results.
If anyone has some other idea please comment, I really appreciate all the input!

[ItsGary]

Originally Posted by strokemycocktus

Thanks everyone for the replies. Unfortunately I wasn't able to run real time diagnosis through inpa, it seems I have some files missing - when I choose MSS60 it throws an error that some data is missing and I only have the basic functions available. In ISTA I have only found a diagnostic routine that I have ran (results above).
However, to me it all seems to be a 'central' electric problem:
1. The limp mode goes on ONLY immediately after a startup when the engine is slightly warm (I drive for 5 mins, engine off, back on - limp mode/ engine is at operating temperature, the car is left with engine off for 30 min - limp mode). Never after a cold start in the morning and never when the engine is fully warmed up.
Engine off and back on gets rid of the limp mode, without even a check engine light.
2. I get a mix of errors (todays readout attached) - O2 sensor, IBS, throttle actuator - but not the typical one (troubleshooting broshure attached).
3. I constantly get water in my battery compartment. All taillight gaskets were replaced, the trunk vent as well. It seems to be leaking somewhere from the side (hence the vent replacement), but I have ran out of ideas. The 'shelf' where all the modules are placed is dry.

I may have a weak battery. I need to check the voltages, charge it overnight and then check again. I'll post the results.
If anyone has some other idea please comment, I really appreciate all the input!

Did you ever get a chance to swap the O2 sensor from one side to the other?

As per the trunk in the water after replacing all those things no clue.

[strokemycocktus]

Originally Posted by ItsGary

Did you ever get a chance to swap the O2 sensor from one side to the other?

As per the trunk in the water after replacing all those things no clue.

Not yet, and I won't have the possibility to get under the car probably until next month. That's why I'd like to try some OBD diagnosis for now.

Yep, water in the trunk drives me crazy. It's only at the bottom of the battery compartment. And it's not that much really.

[ItsGary]

Originally Posted by strokemycocktus

Not yet, and I won't have the possibility to get under the car probably until next month. That's why I'd like to try some OBD diagnosis for now.

Yep, water in the trunk drives me crazy. It's only at the bottom of the battery compartment. And it's not that much really.

Dry it completely. There should be a black rubber circle seal thing that you can pop up to drain the water out. Could be that its missing for you?

[strokemycocktus]

Originally Posted by ItsGary

Dry it completely. There should be a black rubber circle seal thing that you can pop up to drain the water out. Could be that its missing for you?

I dried it several times and put paper towels all around the battery before washing the car - the one under the vent got wet. I probably need to repeat it.
Here is how it looked like the first time I discovered this problem.

[ItsGary]

Originally Posted by strokemycocktus

I dried it several times and put paper towels all around the battery before washing the car - the one under the vent got wet. I probably need to repeat it.
Here is how it looked like the first time I discovered this problem.

You can pop out those rubber drain to help drain it. Could be that one them needs to be replaced or pushed down further