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Discussion Starter #241
Also an update. The Check Engine light appeared yesterday. Car drives fine but no longer pops and bangs.
7289


MGmotorsports said i can “reset this errror and there is a high chance the ecu will adapt and wont show the error again. Also if the error shows again then 2nd oxygen sensor must be readjusted to the existing conditions - it is still not a major tweak and should not void the warranty”.

Thoughts? I’ve ordered this from Amazon to read and clear the fault. Should arrive today. If I clear the fault myself, will merc know or does it affect warranty?
 

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Discussion Starter #242
Apparently the rear sensor was not connected properly which caused the EML to come on. It was plugged back in and the light has gone off.
what error code did this produce? Did you check the Check Engine fault?
 

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Also an update. The Check Engine light appeared yesterday. Car drives fine but no longer pops and bangs.
View attachment 7289

MGmotorsports said i can “reset this errror and there is a high chance the ecu will adapt and wont show the error again. Also if the error shows again then 2nd oxygen sensor must be readjusted to the existing conditions - it is still not a major tweak and should not void the warranty”.

Thoughts? I’ve ordered this from Amazon to read and clear the fault. Should arrive today. If I clear the fault myself, will merc know or does it affect warranty?
I use an app on my phone called car scanner it’s great it may work with the obdu dongle you have ordered, you can use it for free but it’s only about £5 to buy and the guy updates it all the time it’s really useful and works with just about everything. Resetting fault codes shouldn’t cause you any issues with warranty, let us know what you find. The car sounds absolutely wicked, I think I need a down pipe 🤘
 

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Discussion Starter #244
I use an app on my phone called car scanner it’s great it may work with the obdu dongle you have ordered, you can use it for free but it’s only about £5 to buy and the guy updates it all the time it’s really useful and works with just about everything. Resetting fault codes shouldn’t cause you any issues with warranty, let us know what you find. The car sounds absolutely wicked, I think I need a down pipe 🤘
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7292


This is the fault.
P2271
Raw code: 2271
ECU: 58
Status: Confirmed
OBDII: Heated oxygen sensor (HO2S) 2, bank 1 - signal stuck rich

7293


Will it be ok to just clear these and continue as normal?
 

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There was a smell when it was first installed but disappeared after a day. Nothing else since!
The initial smell is the just oil etc. from the manufacturing - nothing to worry about. I'm surprised the car doesn't smell any different tbh. My previous experience of sports cats has been that the smell is pretty obvious compared to stock. Certainly a bonus if you've avoided this!

That code is related to cat emissions rather than the GPF being gone. I'd suspect the 100 cell isn't enough to satisfy the stock mapping's requirements. If that's the case then I can't imagine the ECU ever "learning" to accept the change.

My advice would be the clear the codes, run the car again until the light reappears, then scan it again. You'll often find random codes stored in the history but this method should get rid of everything but the relevant ones.

If it's still throwing up the same code, maybe try sensor spacers: Search "MIL cheater".
 

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I chose this profile?

View attachment 7292

This is the fault.
P2271
Raw code: 2271
ECU: 58
Status: Confirmed
OBDII: Heated oxygen sensor (HO2S) 2, bank 1 - signal stuck rich

View attachment 7293

Will it be ok to just clear these and continue as normal?
Yes clear them and see if it returns, I thought it would be O2 related I had an O2 sensor issue on my old A45 and as you described the pops and bangs all went away, didn’t Joni have this issue and it was just a plug on the sensor come adrift? If not as creed mentioned I think the chances of the ecu learning to accept the new readings will be slim to none unfortunately. Fingers crossed it’s something simple like the plug 🤞
 

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Discussion Starter #248
I cleared the fault on Fri 22nd. Car ran as normal however the engine light came back on Wednesday 27th. When I cleared it again yesterday this is what it showed:

7327

7328

Will it be a problem if I keep clearing the faults every time they come on? Also what is EGR system? This time the Oxygen Sensor Heater also failed.
 

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I cleared the fault on Fri 22nd. Car ran as normal however the engine light came back on Wednesday 27th. When I cleared it again yesterday this is what it showed:

View attachment 7327
View attachment 7328
Will it be a problem if I keep clearing the faults every time they come on? Also what is EGR system? This time the Oxygen Sensor Heater also failed.
The problem with resetting the fault all the time is if it ends up having an actual fault you won’t know, egr means exhaust gas recirculation. Was the car at Running temp when you read the above or cold?
 

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Discussion Starter #250
The problem with resetting the fault all the time is if it ends up having an actual fault you won’t know, egr means exhaust gas recirculation. Was the car at Running temp when you read the above or cold?
ah i see. I think it was running at cold I had driven for about 10 mins but wasn’t normal running temp.
 

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ah i see. I think it was running at cold I had driven for about 10 mins but wasn’t normal running temp.
I wouldn’t worry about the emissions page, just whatever is on the DTC check, which is heated oxygen sensor. Where you able to get it back to the garage to check the connections?
 

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Discussion Starter #252
I wouldn’t worry about the emissions page, just whatever is on the DTC check, which is heated oxygen sensor. Where you able to get it back to the garage to check the connections?
Nope it is a 1hr30 min drive so need to arrange to go down. I googled the EGR system and it operates using a valve which can fail. Is it common for this to show as fail after a downpipe installation?
 

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Nope it is a 1hr30 min drive so need to arrange to go down. I googled the EGR system and it operates using a valve which can fail. Is it common for this to show as fail after a downpipe installation?
This is mine and the egr fails I’m not sure without looking if the car even has egr so I wouldn’t read too much into it, think I’d be tempted to just take it somewhere local and get them to pop it on the ramp and check the O2 sensors are plugged in hunky Dorey save the huge journey just to check a couple of plugs if they are it could just be the fact that with the cat back & the down pipe it’s just too much to cheat the system. Did @joni ever have a EML light come back on?? If so might be worth trying the Mil cheat.


9FCBE04B-18DD-4EEE-A060-B4517F95E45A.png
 

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Discussion Starter #254
Ah do you have a downpipe installed too? Joni got back to me on a PM. He said:

"My EML. has come back on a couple of times since but then went off by itself. My fault was 02 sensor / lean fuel mix, which I presume is due to more air with the downpipes. When this occurred the pops and bangs went. I think the ECU stops the pops and bang when it thinks the fuel air mix is not at the standard level. Pops and bangs came back when I cleared the stored error codes from the ECU.

I have never had the catalyst error or the EGR system - (is that the GPF?) The 02 sensor fault I believe is due to more air in the down pipe.

The second time it happened the EML went of by itself I cleared the codes and the pops and bags came back, but to be honest I can't be asked doing this and need a more perm solution.

I think I will install my chip tune box to see whether this resolves the issue as the box will tell the ECU that the air and fuel etc are all standard levels."
 

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If I clear the fault myself, will merc know or does it affect warranty?
For those who don't know, MB can trace all the information even if it's reverted back to stock. I knew it from my previous AMGs. It will show all the error codes on XENTRY report even it is cleared using OBD port. For instance, if I remove the door puddle lights and install an aftermarket light (projector) that will be shown as well. I have unplugged the exhaust flap module on my E63S so to keep it open all the time. There's no CEL but the error is registered within the ECU with date, time, km, counts, first & last time of occurrence, etc. Some errors may get cleared automatically but they are definitely stored in the system for a reason.
 

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So, lets clear a few things up:

1. A45S does not have an EGR.
2. Clearing DTCs won't damage your vehicle.
3. P2271 is the Lambda sensor on the outgoing side of the cat reporting that there is not enough oxygen present. This could be caused by a faulty sensor. It would also happen if the cat was not filtering as well as expected. I would say it is much more likely that the 100 cell you have had fitted simply isn't doing a good enough job at filtering the emissions.
4. A tuning box will not solve this issue unless it specifically interferes with the sensor causing your EML. You would likely need a bespoke unit for this.
5. As above, all historic fault codes are stored on the vehicle and an ELM327 cannot clear them.

There are 3 possible solutions to this issue:

1. Your downstream Lambda sensor has failed, could have been damaged when it was installed in your new downpipe. Replace this and the car will no longer show an EML (unlikely).
2. Have this sensor mapped out.
3. Try MIL cheaters to reduce the sensor's reading.
 

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I'd recommend clearing all the codes and driving the car again until the EML pops up again. Then re-scan it as soon as you can and post those results.
 
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