[tsn]

Hi
I heard BMW can start a forced OPF regen - is that possible to do with some kind of coding equipment?
What does the regen do, and how to drive?

[M271]

I've had this once or twice on my '23 G87. A few things to note when the regen happens:
- if an auto, it won't hold 8th gear when cruising, it drops to 7th regardless of me trying to attempt a manual change up
- the mpg will plummet as the car goes through a regen

The car works out when one is needed, usually needs a decent long drive to engage this, there are some issues with lots of short journeys clogging up the OPF, resulting in a "stuck" regen. Needs a dealer forced regen if that happens.

Haven't had any issues with mine other than noticing the gear change and mpg reading.

[Matthewricha]

I have a 24 plate car, Manual at 9700 miles and OPF soot levels are 5.18grams. Used to be around 3. I often drive drive longish journeys 45 miles each way and then sometimes up to outskirts of London from the south coast and soot levels never come down. I've even tried the high revs and coming off the accelerator coasting to try and initiate a burn, but no go.

[Bee Pee]

Originally Posted by Matthewricha

I've even tried the high revs and coming off the accelerator coasting to try and initiate a burn, but no go.

Tip from BMW Master Tech - do what you doing but with sport mode and DSC in MDM to create burbles.

Seems some overrun “popcorn” can trigger the OPF regen..

[Matthewricha]

Originally Posted by Bee Pee

Tip from BMW Master Tech - do what you doing but with sport mode and DSC in MDM to create burbles.

Seems some overrun “popcorn” can trigger the OPF regen..

Good to know, will try the MDM mode. I noticed Sport gets the exhaust gases the hottest. Normal and sport plus cooler.

The only way I get to initiate OPF burn is getting the pre-OPF exhaust temperatures to above 700 degrees and rev to 5-7krpm and let off.. only burns of 0.1g per let off for me. Very slow. I have a manual so doesn't obviously affect any 8th gear engagement issues, but you can tell the throttle is a little more sponges when it gets near 5grams of soot.

[Bee Pee]

Originally Posted by Matthewricha

The only way I get to initiate OPF burn is getting the pre-OPF exhaust temperatures to above 700 degrees and rev to 5-7krpm and let off.. only burns of 0.1g per let off for me. Very slow. I have a manual so doesn't obviously affect any 8th gear engagement issues, but you can tell the throttle is a little more sponges when it gets near 5grams of soot.

This is why I had opfs gutted !

The car runs tons better, average mpg went from low/mid 20’s to mid/high 20’s and and gained about 25whp and 30wnmw

[Matthewricha]

Originally Posted by Bee Pee

This is why I had opfs gutted !

The car runs tons better, average mpg went from low/mid 20’s to mid/high 30’s and and gained about 25whp and 30wnmw

Wow, quite the improvement! Where did you get them gutted? Presumably from an MOT perspective they look visually the same. Will consider this or alternatives when my warranty expires.

Our VW Touareg 286ps TDI has an active OPF regen as well as an active DPF regen.. don't see why BMW can't do the same, rather than purely relying upon a passive regen.

[aerobod]

OPF operation may become part of the MOT test in the future, as the MOT standards setting authorities are looking at adding Particle Number testers for DPF tampering detection, that can also be used for detecting OPF tampering: https://mattersoftesting.blog.gov.uk...garages-trial/

[Matthewricha]

Originally Posted by aerobod

OPF operation may become part of the MOT test in the future, as the MOT standards setting authorities are looking at adding Particle Number testers for DPF tampering detection, that can also be used for detecting OPF tampering: https://mattersoftesting.blog.gov.uk...garages-trial/

I guess it would be only a matter of time I suppose 😞.. surprised they don't do it already.

Hello to you in Calgary!! Was there in 2018!

[tsn]

Anyone knows if the valves is foreced open will generate more soot, and/or make it harder to burn the soot out?

[Bee Pee]

Originally Posted by Matthewricha

Wow, quite the improvement! Where did you get them gutted? Presumably from an MOT perspective they look visually the same. Will consider this or alternatives when my warranty expires.

Yes - the s58 is much better wo opf. PCW did the work and underside looks same as stock.

Based on your logs, your soot levels are above what triggers regeneration. The fact that likely it doesn’t take too long to get to above 5 value on both opfs and then the regen does work effectively proves that opf aren’t helping s58 motor at all.

[Bee Pee]

Originally Posted by aerobod

OPF operation may become part of the MOT test in the future, as the MOT standards setting authorities are looking at adding Particle Number testers for DPF tampering detection, that can also be used for detecting OPF tampering: https://mattersoftesting.blog.gov.uk/what-were-working-on-pn-testing-and-cameras-in-garages-trial/

Not convinced.

PN tests on DPF likely easier as values are much much higher ie circa 10 fold for diesel compared to petrol engines.

With lower PN for petrol engines - measuring accuracy is likely to be much harder/costlier to maintain - ie juice is not worth the squeeze.

Diesels with high soot %age in DPFs either perform badly and or are like the proverbial “rolling coal” when regen eventually happens 😂

[aerobod]

Originally Posted by Bee Pee

Not convinced.

PN tests on DPF likely easier as values are much much higher ie circa 10 fold for diesel compared to petrol engines.

With lower PN for petrol engines - measuring accuracy is likely to be much harder/costlier to maintain - ie juice is not worth the squeeze.

Diesels with high soot %age in DPFs either perform badly and or are like the proverbial “rolling coal” when regen eventually happens 😂

There are combined DPF/OPF measurement solutions on the market at the moment, for example: https://pegasor.fi/news/field-proven...-and-gasoline/

The EU regulating bodies are also being urged to adopt annual DPF and GPF (OPF] testing, which would make test equipment more readily available if adopted: https://ec.europa.eu/info/law/better...ge/F3575673_en