[bmwdiesel]

i had to change this post to keep it clear and typos as I was typing on mobile, so the question is, have u felt immediate power gain from removing EGR ? or anyone had a chance to compare hp pre and post removal? I just want to establish the claim that implies it will improve power of the engine, however I don't see how would engine get power from this mod. I can see power increase from removing DPF filter along with appropriate ECU tuning, but want to hear if anyone feels increase performance from removing EGR.
thanks

[RL18]

Egr + air = sooty air for engine

No egr + air = clean oxygen rich air for engine

Which do you think makes more power?

Is it a huge noticeable gain? Probably not but if I were my car I'd rather be inhaling clean air then breathing half air and have out of my ass...

[robnitro]

Egr is not used when under high throttle. It won't limit your max power, but it does clog things up.

[Tambohamilton]

Originally Posted by robnitro

Egr is not used when under high throttle. It won't limit your max power, but it does clog things up.

This.

[Thecastle]

nope. No difference in feel.

[robnitro]

I'm confused as to tuners outside North America... Why do they tune out dpf but not egr? Odd because a few uk members had that issue too.

[bmwdiesel]

Originally Posted by robnitro

I'm confused as to tuners outside North America... Why do they tune out dpf but not egr? Odd because a few uk members had that issue too.

because it removes the back pressure out of turbos and it needs to be adjusted so they won't swirl too much without having that back pressure that DPF creates (at least to my understanding)

btw thank you all for clarifying this for me, because one youtuber was very passionate about removing EGR and how much power you will gain from it. yes he was speaking about BMW diesel...I think it was 535d or 530d, but it's the same as I thought, there isn't any power gain from it, just cleaner air...

[lnxguy]

Anyone who says they feel more power from removing the EGR is full of shit.

[robnitro]

Originally Posted by bmwdiesel

because it removes the back pressure out of turbos and it needs to be adjusted so they won't swirl too much without having that back pressure that DPF creates (at least to my understanding)

btw thank you all for clarifying this for me, because one youtuber was very passionate about removing EGR and how much power you will gain from it. yes he was speaking about BMW diesel...I think it was 535d or 530d, but it's the same as I thought, there isn't any power gain from it, just cleaner air...

I know that about dpf but why do tuners keep egr? Egr is one of the biggest problems with accumulation of soot when it combines with ccv oily gasses.

[Tambohamilton]

Maybe environmental concern? If/when I have my 330d mapped, I won't be removing egr or dpf... I just don't need the maintenance or power gain enough to justify damaging the environment any more than I do already.

[lnxguy]

Originally Posted by robnitro

I know that about dpf but why do tuners keep egr? Egr is one of the biggest problems with accumulation of soot when it combines with ccv oily gasses.

Because it's tuned out (ie closed all the time) If it wasn't, then I'd reconsider your tuning choices, lol.

[bmwdiesel]

Originally Posted by Tambohamilton

Maybe environmental concern? If/when I have my 330d mapped, I won't be removing egr or dpf... I just don't need the maintenance or power gain enough to justify damaging the environment any more than I do already.

i believe removing egr has minimal or none effect on environment, due to the fact that there is DPF for this reason. I believe egr is there to actually save DPF from clogging.

and that's my question, will removing EGR clog up and kill DPF or putting it into the constant or very frequent regeneration cycle that as well restricts performance...??

but to comment again on ur thing, i am more than certain that no i dont think egr will do anything to ennvironment. (CAT and DPF will do the job)

[Tambohamilton]

No. EGR is used specifically to reduce combustion temperature, which limits formation of highly polluting NOx compounds. It has nothing to do with the DPF, which filters out soot (carbon particles) from exhaust gases. The cat is integrated into the DPF, as you mention, but it cannot help with NOx which has already formed in the combustion chamber; it only helps convert CO to CO2, and burn any unburnt fuel that gets there.

EGR will only affect the DPF if it affects the fuelling. For example if the DDE throws a wobbly and starts over fuelling when EGR is blanked off....but I doubt that would happen.

[robnitro]

Egr off is less soot more NOx. Better for dpf life as less unburned particles get collected. However, make sure the tuner can properly do this because stock tune uses egr and throttle valve for regens.

[geko29]

I can't say for sure because I changed two things at once. But I went from EGR electrically disabled (paperclip mod) and a JBD, to EGR fully blocked off with a race pipe and a DUDMD tune. Power delivery is definitely smoother now, and it seems like the car "coasts" faster if that makes any sense. Like if I'm driving in traffic and let off the gas to keep from overtaking the car in front of me, I have to get on the brakes much sooner now than I used to, whereas before maybe I could just be off the gas for 10 seconds or so and then could gradually get back on it.

[MDeeJs]

I was EGR deleted only for 8 months.
No increased power
No increased MPG either
as many claimed they have better mpg, it's a BS

Tested on my X5 and my 335.
Both cars were tuned for EGR delete only ( no check engine light, no codes )

[Tambohamilton]

Yeah, EGR doesn't affect the running of the engine - MPG or power - other than fouling the inlet; it's an emissions device only. It's specifically programmed to only operate at part throttle and cruise conditions, so it simply doesn't affect response or power. It also doesn't affect efficiency...there simply isn't any reason for it to. All it does is reduce the peak combustion temperature by effectively enriching the AFR.

Geko29 does put up an interesting point though; part of the egr system is the throttle butterfly, which I had often wondered if BMW programmed to increase engine braking (diesels have reduced engine braking compared with a similar petrol engine, due to the lack of a throttle valve). If his observations are correct, that's pretty interesting. I wonder if egr could be programmed out, but control of the butterfly on decel left in...

[lnxguy]

That throttle butterfly is the ASV. It's not used for anything but engine shutdown. Anti Shudder Valve During normal engine operation, it's not doing anything.

[Tambohamilton]

Interesting. Got a link to more info? Realoem just calls it 'throttle', as do most places selling it...couldn't find anything interesting about it in a 5 min search.

[Yozh]

It’s also used for DPF regeneration.