[KnobDE]

I recently replaced my turbos and much more on my e92 n54 and noticed my car is way more quieter than it was before, MHD stage 2 was on the car before I changed so much. I thought it may because of new seals, but for logging purposes I flashed back to Stage 0 stock through MHD to keep the data logging active.

With that it is much more louder, it bangs and pops like it used to.

Next to the turbos I replaced boost solenoids, coils, spark plugs, ton of seals and hoses and so on...

Is that something with the wastegates? They´re not that wide open with stage 2? Even with aggresive pops and bang settings, it gets not very loud (also while normal driving).

And another thing, my car never wanted to burble above 3000 rpms, even after replacing so much, never understood why...?

[Saif2018]

Originally Posted by KnobDE

I recently replaced my turbos and much more on my e92 n54 and noticed my car is way more quieter than it was before, MHD stage 2 was on the car before I changed so much. I thought it may because of new seals, but for logging purposes I flashed back to Stage 0 stock through MHD to keep the data logging active.

With that it is much more louder, it bangs and pops like it used to.

Next to the turbos I replaced boost solenoids, coils, spark plugs, ton of seals and hoses and so on...

Is that something with the wastegates? They´re not that wide open with stage 2? Even with aggresive pops and bang settings, it gets not very loud (also while normal driving).

And another thing, my car never wanted to burble above 3000 rpms, even after replacing so much, never understood why...?

Stage 0 should be quieter than Stage 2, because your WGDC will be lower and you won't hear thw turbo spool as much.

How is your Exhaust setup?

[KnobDE]

In my case I got the opposit, Stage 0 is much louder (counts for burbles and normal driving).

VRSF downpipes, nothing else, and exhaust flap is always open.

[Smgs1992]

Never flashed to stage 0 but my car FBO before tuning was much much quieter than afterwards. It really surprised me how much louder and more like a tuner car it sounded like afterwards. From the spool and the wastegates, induction sound, DV’s and everything.

[KnobDE]

I have no idea what´s wrong then

Maybe too much psi and leaking/passing anywhere...? I logged the car with stage 2 and actual boost was always 0,2-0,3bar (3-4,3psi) behind target boost, Stage0 is fine

[Tyc0]

I noticed this whenever my car would go into limp mode(turbos off). The pops and bangs sounded like legitimate gun shots. I think it has something to do with the fact that the turbos are pushing out more air when the boost is higher, or they are just drowning out these sounds completely.

[Saif2018]

Originally Posted by KnobDE

I have no idea what´s wrong then

Maybe too much psi and leaking/passing anywhere...? I logged the car with stage 2 and actual boost was always 0,2-0,3bar (3-4,3psi) behind target boost, Stage0 is fine

That's likely a boost leak.

[KnobDE]

I guess so, need to find out where it´s coming from then, things like tmap sensor, boost solenoids, plugs, coils and so on are new

[Saif2018]

Originally Posted by KnobDE

I guess so, need to find out where it´s coming from then, things like tmap sensor, boost solenoids, plugs, coils and so on are new

Follow this guide..

https://bmwtuning.co/bmw-n54-30ff-en...-repair-guide/

[KnobDE]

1. Inspect piping for the intake, chargepipe, diverter valves
As I said, I already did that.

2. Check your vacuum lines
They´re all new.

3. Replace your N54 boost solenoids
I did, they´re new, 2x Pierburg.

4. Adjust your wastegate actuators
Turbos are new.

5. Replace your turbos
That´s what I did

[studio54]

Originally Posted by Tyc0

I noticed this whenever my car would go into limp mode(turbos off). The pops and bangs sounded like legitimate gun shots. I think it has something to do with the fact that the turbos are pushing out more air when the boost is higher, or they are just drowning out these sounds completely.

I believe that when the car goes into limp mode, wastegate gets 100% open and maybe DME runs richer as a security feature, that's why it sounds louder with a lot of pops/bangs.

[Saif2018]

Originally Posted by KnobDE

1. Inspect piping for the intake, chargepipe, diverter valves
As I said, I already did that.

2. Check your vacuum lines
They´re all new.

3. Replace your N54 boost solenoids
I did, they´re new, 2x Pierburg.

4. Adjust your wastegate actuators
Turbos are new.

5. Replace your turbos
That´s what I did

lol so is the boost leak fixed?

[KnobDE]

Nah dude, still looking for it But I don´t have the stuff to do a boost leak test

[ewicky]

You said:

Originally Posted by KnobDE

Stage 0 is much louder

Title of this thread:

MHD Stage0 much quieter than Stg2

So which one is it?

[KnobDE]

Sorry, didnt see that, Stage 0 is much louder, Stage 2 is the quiet one

[ewicky]

Originally Posted by KnobDE

Sorry, didnt see that, Stage 0 is much louder, Stage 2 is the quiet one

What type of noise gets louder? If you're referring to exhaust note:

Higher the stage, higher the boost. Higher boost means closed wastegates. Closed wastegates forces exhaust thru the turbo, softening the noise. Less boost = open wastegates = direct path for exhaust.

With JB4, there's a valet MAP that disables boost entirely by opening the wastegates and leaving them open. It's like Stage -1. It makes the engine sound much deeper, better, louder. Also is slightly more efficient since it reduces exhaust back pressure when it isn't' needed to spool.

[Saif2018]

Originally Posted by KnobDE

Nah dude, still looking for it But I don´t have the stuff to do a boost leak test

Have you checked the vacumn cannisters, sometimes the connection points crack.

Take it to a garage and get a boost leak done.

[KnobDE]

Vacuum canisters are fine, on of first things I checked

But compared to other cars with Stage 2 mine is way different, but I guess there´s still a boost leak, here in Germany I couldn´t find a proper shop yet, which could do me a boost leak test, BMW said I should give them my car there for a few days. Somehow I got the feeling they do not really know what to do then..

[BSM n54iS]

Do you have a decibel-O-meter on your phone? I'm gonna have to see some numbers here..

[KnobDE]

I can make you a video in neutral, if you want

For comparison... anyone in here got a vid with stage 2, downpipes and oem exhaust in neutral or while driving?

[Saif2018]

Originally Posted by KnobDE

Vacuum canisters are fine, on of first things I checked

But compared to other cars with Stage 2 mine is way different, but I guess there´s still a boost leak, here in Germany I couldn´t find a proper shop yet, which could do me a boost leak test, BMW said I should give them my car there for a few days. Somehow I got the feeling they do not really know what to do then..

BMW will most likely screw you over and charge you through the nose, would recommend you stay away from them. Wouldn't be surprised if some of the mechanics or after sales people are clueless either.

If the turbos are new, you almost certainly have a boost leak somewhere, 3-4 psi off target isn't normal, 1-2 at worst. Definitely need to do a boost leak test.

The turbos you replaced, they stock OEM ones?

Did you have a local garage install them or did BMW?

[KnobDE]

These are OEM MHI (Mitsubishi) turbos.

A local shop did it for me, they did a lot to my car in the past and I was always more than pleased, but this time I´m still struggling to get them fix this for me, didn´t pay anything yet to them tho ..

Wednesday (9.12) I´ll let my car check with smoke, to find the boost leak, also they will check if everything was installed properly (A/C is already empty, it wasn´t really tight under the air box).

Another thing I noticed with stage 2, if I start the car in the morning and start driving, it howls pretty loud, coming from the turbos, I don´t have that with Stage 0. Either its a hard boost leak or on of the turbos is already trash