BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read
M2 Technical Topics > S55 Engine / Drivetrain / Exhaust / Bolt-ons / Tuning > OPF Removal: CEL or Limp Mode?

Post Reply
 
Thread Tools Search this Thread
      02-07-2019, 03:47 PM   #23
cecaa850
Captain
United_States
259
Rep
699
Posts

Drives: 2018 M2
Join Date: May 2018
Location: South East TX.

iTrader: (0)

Quote:
Originally Posted by MR. View Post
You can also try to reach the pressure difference sensor box and disconnect it. It is a small black box on top of one of the downpipes.

MR
I would think that doing that would trigger a circuit code. It would be nice to know exactly what pressures it's actually trying to see or if it's just looking for a certain pressure differential.
Appreciate 0
      02-07-2019, 05:02 PM   #24
Billy_BMW
Private First Class
United Kingdom
52
Rep
138
Posts

Drives: BMW M2 Competition
Join Date: Feb 2012
Location: UK

iTrader: (0)

Guys we really do need an easier solution than to resort to remapping. Very keen to know how you get on gents; please keep us updated.

The annoying thing is that non-EU M2C’s sound much better with even secondary cats still in place; go aftermarket and the sound difference is staggering.
Appreciate 0
      02-07-2019, 06:01 PM   #25
MR.
Colonel
MR.'s Avatar
No_Country
4397
Rep
2,856
Posts

Drives: BMW M2 CSL Turbomeister
Join Date: Sep 2013
Location: Travelling / Managing / Writing

iTrader: (0)

Garage List
Quote:
Originally Posted by Billy_BMW View Post
Guys we really do need an easier solution than to resort to remapping. Very keen to know how you get on gents; please keep us updated.

The annoying thing is that non-EU M2C’s sound much better with even secondary cats still in place; go aftermarket and the sound difference is staggering.
I will share more when I can with regards to the product idea for the OPF delete. The aim is no more ECU tuning to remove the OPFs.

MR
Appreciate 0
      02-08-2019, 02:33 AM   #26
doughboy
Major General
doughboy's Avatar
1543
Rep
8,972
Posts

Drives: 2018 M2 Comp 6MT
Join Date: Jan 2009
Location: UK

iTrader: (2)

Yes that was my plan. Its just a rubber hose onto the pressure sensor. ( 1 per opf)
Appreciate 0
      02-08-2019, 03:32 AM   #27
Bee Pee
Brigadier General
United Kingdom
1738
Rep
4,496
Posts

Drives: AW M2 DCT
Join Date: Jun 2010
Location: SW London

iTrader: (3)

Quote:
Originally Posted by doughboy View Post
I'm considering Decat DPs (which are cheap) then add non EU midpipes with secondary CATs (to pass UK emissions test). This depends on price of secondary CATs as spare parts..
DB,

Once OPF limp code is understood/worked around, would it not be cheaper/easier to fit sport cat DP's and then gut OPF of OEM midpipe ?

Then, visually OPF looks in situ and running sport cat DP's should get S55 though emissions test perhaps ?

BP
__________________
Fettled M135i EB AT - gone but not forgotten:
AW M2 DCT
Appreciate 0
      02-08-2019, 03:37 AM   #28
MR.
Colonel
MR.'s Avatar
No_Country
4397
Rep
2,856
Posts

Drives: BMW M2 CSL Turbomeister
Join Date: Sep 2013
Location: Travelling / Managing / Writing

iTrader: (0)

Garage List
Quote:
Originally Posted by Bee Pee View Post
DB,

Once OPF limp code is understood/worked around, would it not be cheaper/easier to fit sport cat DP's and then gut OPF of OEM midpipe ?

Then, visually OPF looks in situ and running sport cat DP's should get S55 though emissions test perhaps ?

BP
That is not going to work. You will change back pressure which will make sure the sensors throw your car in an error.

Also a sport car DP will not fit in the space next to the engine I heard (not 100% sure), so those are not an option, next to the fact that you put too much strain on the OPFs.

You can change whatever you want, but it are the sensors at the end of the downpipes that are the issue not the OPF itself. The trick is to fool the car the sensors are reading the right back pressure or make sure that what they read is not taken in consideration by the ECU.

If you have created that set up you can what you want. Emission testing is not applicable now. Your MOT is three years away.

MR
Appreciate 0
      02-08-2019, 03:56 AM   #29
doughboy
Major General
doughboy's Avatar
1543
Rep
8,972
Posts

Drives: 2018 M2 Comp 6MT
Join Date: Jan 2009
Location: UK

iTrader: (2)

Sport cat DPs re about £2500-3000 compared to under £500 for Decats.

The way i see it, fit a US mid pipe with sec cats to pass MOT and they would also pass as OPF for visual inspection too. My old n54 335i flew the MOT with only secondary cats.

Decat DPs. Win win. Sound, power etc. It would sound great and maybe sec cat back pressure would give less problems with OPF sensors who knows?

Yes MOT is 2.5 years away but it needs considering now really to avoid big bills & problems then.

Only problem is non EU mid pipe is £2450 after discount.... Maybe buy used from US guys?
Appreciate 0
      02-08-2019, 05:18 AM   #30
MR.
Colonel
MR.'s Avatar
No_Country
4397
Rep
2,856
Posts

Drives: BMW M2 CSL Turbomeister
Join Date: Sep 2013
Location: Travelling / Managing / Writing

iTrader: (0)

Garage List
Quote:
Originally Posted by doughboy View Post
Sport cat DPs re about £2500-3000 compared to under £500 for Decats.

The way i see it, fit a US mid pipe with sec cats to pass MOT and they would also pass as OPF for visual inspection too. My old n54 335i flew the MOT with only secondary cats.

Decat DPs. Win win. Sound, power etc. It would sound great and maybe sec cat back pressure would give less problems with OPF sensors who knows?

Yes MOT is 2.5 years away but it needs considering now really to avoid big bills & problems then.

Only problem is non EU mid pipe is £2450 after discount.... Maybe buy used from US guys?
This is playing with fire. Who says that this new set up you mention above is EURO6 compliant when they test it in 2.5 years?

Be aware that the EURO6 regulations are different to the EURO4 or EURO5 regulations of your N54 335i. There is a reason you have OPFs to pass EURO6. If we did not need those OPFs to pass, then they would not be on the car.

I don't believe that you will pass MOT in 2.5 years with only a US linkpipe with secondary cats. I think your car will fail, since it is not EURO6 compliant on the emissions which will be measured by then.

I hope you see my point. I think you are looking for the cheap route here, which isn't a solution imo. Doesn't mean you can get the linkpipe from the U.S., but it doesn't make your car compliant to EURO6, because your emissions are still worse than you have now. Also your car is not CoC compliant and therefore illegal since the measured emission level is not the same as on your CoC paperwork.

It would be wonderful what you say, but I have my doubts you get away with it. They can't measure EURO6 now at the MOT since it is not required, but I can ensure you in 2.5 years they will and it will be freaking strict.

Of course, all becomes different if you guys can finally make up your mind about leaving the EU.

MR
Appreciate 0
      02-08-2019, 05:41 AM   #31
doughboy
Major General
doughboy's Avatar
1543
Rep
8,972
Posts

Drives: 2018 M2 Comp 6MT
Join Date: Jan 2009
Location: UK

iTrader: (2)

In theory MR you are right, but in the UK (and may other places) the annual emissions checks are just a very loose functional check of CATs and hydrocarbon emissions / lamda readings.

More recent checks for integrity of emissions systems are "visual inspection" only and covers etc are not to be removed (engine undertrays for example). There will be no OPF test in the same way there is no DPF test.

My 335i was well inside the test limits with only Secondary CATs because the test limits have barely changed since 1996 when CATs test was introduced. The test is to detect NO or failed CATs only, not the check type approval level!

It is not possible for a regular garage to test to the relevant EURO4/5/6 limits, you would need very expensive equipment, almost laboratory conditions and well trained technicians - This is exactly what you average back street MOT garage does not ever have and the government would never pay for it either.

...so back on thread... secondary CATs would pass MOT, but we still need to deal with OPF detection on the car...

EDIT: I've just checked MOT data, and the N54 335i has a CO pass limit of 0.2% (which mine passed with only sec cats at less than 0.1%). But the S55 F80 M3 has a CO limit of 0.3% - so 50% higher than the old N54 engine!

Good old MOT

Last edited by doughboy; 02-08-2019 at 07:12 AM..
Appreciate 0
      02-08-2019, 07:02 AM   #32
Bee Pee
Brigadier General
United Kingdom
1738
Rep
4,496
Posts

Drives: AW M2 DCT
Join Date: Jun 2010
Location: SW London

iTrader: (3)

Quote:
Originally Posted by Bee Pee
DB,

Once OPF limp code is understood/worked around, would it not be cheaper/easier to fit sport cat DP's and then gut OPF of OEM midpipe ?

BP
Quote:
Originally Posted by MR. View Post
That is not going to work. You will change back pressure which will make sure the sensors throw your car in an error.

Also a sport car DP will not fit in the space next to the engine I heard (not 100% sure), so those are not an option, next to the fact that you put too much strain on the OPFs.
Marc - shame you didn't read my post properly as I say the tricks required to code out CEL/error/limp mode are assumed in place and that gutting OPF - same principle as gutting cat pipes - removes the brick blocking the exhaust but looks OEM...

Also sport cats DP not fitting - doubtful else why do LW in Germany offer them for M2Comp ? BP

BP

Quote:
Originally Posted by doughboy View Post
Sport cat DPs re about £2500-3000 compared to under £500 for Decats.

Only problem is non EU mid pipe is £2450 after discount.... Maybe buy used from US guys?
DB - yes LW charge £3k for their catted DP's but the likes of Milltek sell catted DP's for s55 for half this price....BP
__________________
Fettled M135i EB AT - gone but not forgotten:
AW M2 DCT
Appreciate 0
      02-08-2019, 07:43 AM   #33
MR.
Colonel
MR.'s Avatar
No_Country
4397
Rep
2,856
Posts

Drives: BMW M2 CSL Turbomeister
Join Date: Sep 2013
Location: Travelling / Managing / Writing

iTrader: (0)

Garage List
Quote:
Originally Posted by Bee Pee View Post
Marc - shame you didn't read my post properly as I say the tricks required to code out CEL/error/limp mode are assumed in place and that gutting OPF - same principle as gutting cat pipes - removes the brick blocking the exhaust but looks OEM...

Also sport cats DP not fitting - doubtful else why do LW in Germany offer them for M2Comp ? BP

DB - yes LW charge £3k for their catted DP's but the likes of Milltek sell catted DP's for s55 for half this price....BP
I did not really follow your initial post. Read it twice, but wasn't 100% sure what you meant

Interesting on the catted DP's. Great feedback. Someone was talking to me about it and said it would not fit, which I was a bit like "really" about. Uhmmm, as I said, not 100% sure on that one.

I believe you immediately that is available. I have just not seen it anywhere. In the end, I am not going for the sport downpipe, I don't really see the benefit for it with my current set up.

MR

Last edited by MR.; 02-08-2019 at 07:49 AM..
Appreciate 0
      02-08-2019, 07:48 AM   #34
MR.
Colonel
MR.'s Avatar
No_Country
4397
Rep
2,856
Posts

Drives: BMW M2 CSL Turbomeister
Join Date: Sep 2013
Location: Travelling / Managing / Writing

iTrader: (0)

Garage List
Quote:
Originally Posted by doughboy View Post
In theory MR you are right, but in the UK (and may other places) the annual emissions checks are just a very loose functional check of CATs and hydrocarbon emissions / lamda readings.

More recent checks for integrity of emissions systems are "visual inspection" only and covers etc are not to be removed (engine undertrays for example). There will be no OPF test in the same way there is no DPF test.

My 335i was well inside the test limits with only Secondary CATs because the test limits have barely changed since 1996 when CATs test was introduced. The test is to detect NO or failed CATs only, not the check type approval level!

It is not possible for a regular garage to test to the relevant EURO4/5/6 limits, you would need very expensive equipment, almost laboratory conditions and well trained technicians - This is exactly what you average back street MOT garage does not ever have and the government would never pay for it either.

...so back on thread... secondary CATs would pass MOT, but we still need to deal with OPF detection on the car...

EDIT: I've just checked MOT data, and the N54 335i has a CO pass limit of 0.2% (which mine passed with only sec cats at less than 0.1%). But the S55 F80 M3 has a CO limit of 0.3% - so 50% higher than the old N54 engine!

Good old MOT
All I can say is really interesting! I heard from the German market that there all is going upside down on this matter, due to the link with the taxes and because everyone has gone completely mental due to dieselgate.

I was not aware of the UK systems, but if it is that easy then bring it on. This seems to be easier than I initially thought, but then again let's just hope they aren't going to update any of the systems like in Germany. It is freaking 2.5 years away.

Can you imagine what happens if in the news drops that all cars might be EURO6, but there is no way to test that during a MOT? It would become MOTgate. Everyone is so stressed about emissions everywhere... Pfff meanwhile plans are flying more and more and oil tankers are pushing out worse gasses into the sky.

Feels like the German market is leading on this matter again and the other markets are far behind and not even following yet. I wonder if my current set up is even "homologated" in my country, because we are further behind then the rest of Europe on this matter.

Thanks for the explanation. Learned something new about the UK.

MR
Appreciate 0
      02-08-2019, 11:07 AM   #35
Billy_BMW
Private First Class
United Kingdom
52
Rep
138
Posts

Drives: BMW M2 Competition
Join Date: Feb 2012
Location: UK

iTrader: (0)

Very interesting discussion - just to explain, my primary reason for removing them is sound. I’m hoping for a slight improvement in throttle response as well. I know the S55 isn’t universally liked for its sound but it would still be nice to have some of the ‘violence’ and snarl of the CS/GTS cars. For me, the midpipe is where the biggest restriction happens - you can put whatever backbox takes your fancy but I can’t stand these bricks killing the sound!
Appreciate 0
      02-08-2019, 02:17 PM   #36
doughboy
Major General
doughboy's Avatar
1543
Rep
8,972
Posts

Drives: 2018 M2 Comp 6MT
Join Date: Jan 2009
Location: UK

iTrader: (2)

MR, in the UK there was uproar a few year ago at diesel owners removing diesel particulate filters when they failed to avoid the high cost of new ones, the same will happen with OPF in time. (Do you know our OPFs will need replacing in 60,000 to 100,000 miles at owners cost).

That is when they introduced the "visual inspection" of emissions equipment to the MOT and also made it illegal to sell remaps to specifically remove emissions equipment. So the MOT relies on visual checks and lack of any CEL. No OBD check's are included...

Last edited by doughboy; 02-08-2019 at 02:28 PM..
Appreciate 0
      02-08-2019, 02:27 PM   #37
doughboy
Major General
doughboy's Avatar
1543
Rep
8,972
Posts

Drives: 2018 M2 Comp 6MT
Join Date: Jan 2009
Location: UK

iTrader: (2)

Billy_BMW

For me the S55 is the descendant of the N54 rather than the N55,

The N54 had twin turbos with separate exhausts all the way just like the S55 and it sounded just awesome with decat DPs and standard rest of system. Deep, rorty, great sound from the thin-walled DP's.

If I can make the M2C sound like my N54 335i I'll be a happy man.
Appreciate 0
      02-08-2019, 03:00 PM   #38
MR.
Colonel
MR.'s Avatar
No_Country
4397
Rep
2,856
Posts

Drives: BMW M2 CSL Turbomeister
Join Date: Sep 2013
Location: Travelling / Managing / Writing

iTrader: (0)

Garage List
Quote:
Originally Posted by doughboy View Post
MR, in the UK there was uproar a few year ago at diesel owners removing diesel particulate filters when they failed to avoid the high cost of new ones, the same will happen with OPF in time. (Do you know our OPFs will need replacing in 60,000 to 100,000 miles at owners cost).

That is when they introduced the "visual inspection" of emissions equipment to the MOT and also made it illegal to sell remaps to specifically remove emissions equipment. So the MOT relies on visual checks and lack of any CEL. No OBD check's are included...
Interesting! Good to know this.

Quote:
Originally Posted by doughboy View Post
Billy_BMW

For me the S55 is the descendant of the N54 rather than the N55,

The N54 had twin turbos with separate exhausts all the way just like the S55 and it sounded just awesome with decat DPs and standard rest of system. Deep, rorty, great sound from the thin-walled DP's.

If I can make the M2C sound like my N54 335i I'll be a happy man.
Did you have the issues with the waste gates? I had my turbos replaced twice on 150K km... Every 50K km the waste gates actuators had too much movement and you heard them rattling.

And I ran 450 hp and 600 Nm on my 135i, which meant that the car went in limp mode because the actuators got stuck because they could not keep up with the required faster movement.

MR
Appreciate 0
      02-08-2019, 05:18 PM   #39
Billy_BMW
Private First Class
United Kingdom
52
Rep
138
Posts

Drives: BMW M2 Competition
Join Date: Feb 2012
Location: UK

iTrader: (0)

Quote:
Originally Posted by doughboy View Post
Billy_BMW

For me the S55 is the descendant of the N54 rather than the N55,

The N54 had twin turbos with separate exhausts all the way just like the S55 and it sounded just awesome with decat DPs and standard rest of system. Deep, rorty, great sound from the thin-walled DP's.

If I can make the M2C sound like my N54 335i I'll be a happy man.
Definitely agree on the lineage - the S55 is very sensitive to exhaust setup; some combos it sounds horrible, raspy and lawnmower-like. In milder combos, it’s actually quite good.

The OPF- spec ones sound shite however 😂
Appreciate 0
      02-08-2019, 05:45 PM   #40
doughboy
Major General
doughboy's Avatar
1543
Rep
8,972
Posts

Drives: 2018 M2 Comp 6MT
Join Date: Jan 2009
Location: UK

iTrader: (2)

Quote:
Originally Posted by MR. View Post
Interesting! Good to know this.



Did you have the issues with the waste gates? I had my turbos replaced twice on 150K km... Every 50K km the waste gates actuators had too much movement and you heard them rattling.

And I ran 450 hp and 600 Nm on my 135i, which meant that the car went in limp mode because the actuators got stuck because they could not keep up with the required faster movement.

MR
It was a 2009 car i bought new. It had minor rattles at 400+bhp long term. Tweaking the JB4 PWM duty cycle settings helped a little. I sold the car at 4 yrs / 55k miles.

The buyer contacted me 4 years later to say the car had been faultless and was the best car he had ever owned!

Praise indeed.
Appreciate 0
      03-11-2019, 07:57 AM   #41
doughboy
Major General
doughboy's Avatar
1543
Rep
8,972
Posts

Drives: 2018 M2 Comp 6MT
Join Date: Jan 2009
Location: UK

iTrader: (2)

Quote:
Originally Posted by MR. View Post
I will share more when I can with regards to the product idea for the OPF delete. The aim is no more ECU tuning to remove the OPFs.

MR
MR, any news on this OPF delete solution??
Appreciate 0
      03-11-2019, 12:46 PM   #42
ingmv
New Member
24
Rep
14
Posts

Drives: BMW F87 M2 Competition
Join Date: May 2007
Location: Austria

iTrader: (0)

Has anyone tried to remove S1DEA from the VO?

And flash the DME ?
Appreciate 0
      03-11-2019, 04:50 PM   #43
Karlosm2c
Lieutenant
Karlosm2c's Avatar
United Kingdom
291
Rep
456
Posts

Drives: M2 Competition
Join Date: Oct 2018
Location: Bedfordshire

iTrader: (0)

Quote:
Originally Posted by Bee Pee View Post
Quote:
Originally Posted by "Bee Pee"
DB,

Once OPF limp code is understood/worked around, would it not be cheaper/easier to fit sport cat DP's and then gut OPF of OEM midpipe ?

BP
Quote:
Originally Posted by MR. View Post
That is not going to work. You will change back pressure which will make sure the sensors throw your car in an error.

Also a sport car DP will not fit in the space next to the engine I heard (not 100% sure), so those are not an option, next to the fact that you put too much strain on the OPFs.
Marc - shame you didn't read my post properly as I say the tricks required to code out CEL/error/limp mode are assumed in place and that gutting OPF - same principle as gutting cat pipes - removes the brick blocking the exhaust but looks OEM...

Also sport cats DP not fitting - doubtful else why do LW in Germany offer them for M2Comp ? BP

BP

Quote:
Originally Posted by doughboy View Post
Sport cat DPs re about £2500-3000 compared to under £500 for Decats.

Only problem is non EU mid pipe is £2450 after discount.... Maybe buy used from US guys?
DB - yes LW charge £3k for their catted DP's but the likes of Milltek sell catted DP's for s55 for half this price....BP
BP (or anyone else who can help with this one),

I'm getting the LightWeight system next month, keeping OPFs. I saw recently their sport downpipes are coming in at just under €3,000 as you mentioned, which isn't ideal. Do you know if alternative downpipes can be interchanged with different exhaust systems, i.e. could I use a Milltek DP with the LightWeight exhaust or would they not line up correctly?

Cheers,

Karl
__________________
2019 HS DCT M2 Competition with Essex AP Racing Radical Pro5000r front and rear BBKs, Bilstein B16s and 763M wheels with Cup 2s
Appreciate 0
      03-11-2019, 05:38 PM   #44
Bee Pee
Brigadier General
United Kingdom
1738
Rep
4,496
Posts

Drives: AW M2 DCT
Join Date: Jun 2010
Location: SW London

iTrader: (3)

Quote:
Originally Posted by Karlosm2c View Post
Quote:
Originally Posted by Bee Pee View Post
Quote:
Originally Posted by "Bee Pee"
DB,

Once OPF limp code is understood/worked around, would it not be cheaper/easier to fit sport cat DP's and then gut OPF of OEM midpipe ?

BP
Quote:
Originally Posted by MR. View Post
That is not going to work. You will change back pressure which will make sure the sensors throw your car in an error.

Also a sport car DP will not fit in the space next to the engine I heard (not 100% sure), so those are not an option, next to the fact that you put too much strain on the OPFs.
Marc - shame you didn't read my post properly as I say the tricks required to code out CEL/error/limp mode are assumed in place and that gutting OPF - same principle as gutting cat pipes - removes the brick blocking the exhaust but looks OEM...

Also sport cats DP not fitting - doubtful else why do LW in Germany offer them for M2Comp ? BP

BP

Quote:
Originally Posted by doughboy View Post
Sport cat DPs re about £2500-3000 compared to under £500 for Decats.

Only problem is non EU mid pipe is £2450 after discount.... Maybe buy used from US guys?
DB - yes LW charge £3k for their catted DP's but the likes of Milltek sell catted DP's for s55 for half this price....BP
BP (or anyone else who can help with this one),

I'm getting the LightWeight system next month, keeping OPFs. I saw recently their sport downpipes are coming in at just under €3,000 as you mentioned, which isn't ideal. Do you know if alternative downpipes can be interchanged with different exhaust systems, i.e. could I use a Milltek DP with the LightWeight exhaust or would they not line up correctly?

Cheers,

Karl
Karl

It's usual for aftermarket DPs to fit stock exhaust and aftermarket exhausts to fit stock DPs.

Safe to assume that aftermarket DPs and aftermarket exhausts are cross compatible.

BP
__________________
Fettled M135i EB AT - gone but not forgotten:
AW M2 DCT
Appreciate 0
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 01:24 PM.




m2
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST