[AB M2C]

Looking for some guidance on what might be going on with my 2019 M2C. The car seems down on power. No codes are being thrown.

So other than the feel that the car is relatively slow the biggest hint I have that something is wrong, is when the car initially tries to go into boost, there is a whooshing sound. I've tried to grab a sound clip of it, but it only does it under load, and the other noises are too loud for a camera mic to pick up.

Anyway at 3k-4.5k rpms at about 3 times a second there is an audible whoosh, whoosh, whoosh sound, especially noticeable in 3rd-6th gears.

This made me initially think boost leak. I know the plastic boost pipes are prone to failure, so i replaced those with some aluminum ones, yet the sound is there and the car feels the same. Is there a possibility of a vacuum leak? I can't find a broken line anywhere, but maybe i'm missing something?

Other symptoms: I have a carbahn stage 1 tune that ... allegedly... makes 560 HP... I know this isn't a great or very realistic test but its some data point, the "sports display" in the car shows the exact same Horsepower going from the stock tune to the Carbahn Tune. both of which are at about 340HP...

My butt dyno puts the car somewhere around 300HP too.

Has anyone else had this issue? Literally any guidance would be appreciated as I am kind of at a loss.

I took the car to a dealer as its under warranty and they were like well it didn't throw a code so we can't help you, great service right?

Anyway if anyone has any thoughts at this point i'm all ears.

[///MPECABL]

Originally Posted by AB M2C

Looking for some guidance on what might be going on with my 2019 M2C. The car seems down on power. No codes are being thrown.

So other than the feel that the car is relatively slow the biggest hint I have that something is wrong, is when the car initially tries to go into boost, there is a whooshing sound. I've tried to grab a sound clip of it, but it only does it under load, and the other noises are too loud for a camera mic to pick up.

Anyway at 3k-4.5k rpms at about 3 times a second there is an audible whoosh, whoosh, whoosh sound, especially noticeable in 3rd-6th gears.

This made me initially think boost leak. I know the plastic boost pipes are prone to failure, so i replaced those with some aluminum ones, yet the sound is there and the car feels the same. Is there a possibility of a vacuum leak? I can't find a broken line anywhere, but maybe i'm missing something?

Other symptoms: I have a carbahn stage 1 tune that ... allegedly... makes 560 HP... I know this isn't a great or very realistic test but its some data point, the "sports display" in the car shows the exact same Horsepower going from the stock tune to the Carbahn Tune. both of which are at about 340HP...

My butt dyno puts the car somewhere around 300HP too.

Has anyone else had this issue? Literally any guidance would be appreciated as I am kind of at a loss.

I took the car to a dealer as its under warranty and they were like well it didn't throw a code so we can't help you, great service right?

Anyway if anyone has any thoughts at this point i'm all ears.

I've seen multiple occurrences of the J-pipe under the charge cooler coming off. May want to check there as well, both at the charge cooler and the manifold. Symptoms and whoosh sound make my think boost leak.

[AB M2C]

Originally Posted by ///MPECABL

I've seen multiple occurrences of the J-pipe under the charge cooler coming off. May want to check there as well, both at the charge cooler and the manifold. Symptoms and whoosh sound make my think boost leak.

Awesome, this is good to know and I was going to check that, I just hadn't found much saying those pipes fail too, and decided that was a lot more effort than just replacing the boost pipes.

I purchased the kit that also has a metal j-pipe so i'll replace and inspect that later today.

Thanks for the reply.

[AB M2C]

Well... I replaced the jpipe and the same noise and symptoms are still present. Is it possible the wastegates are quickly opening and closing when going into boost? or maybe the intercooler has failed? thats the last piece in the pressurized boost line.

[///MPECABL]

Originally Posted by AB M2C

Well... I replaced the jpipe and the same noise and symptoms are still present. Is it possible the wastegates are quickly opening and closing when going into boost? or maybe the intercooler has failed? thats the last piece in the pressurized boost line.

How's your coolant levels for the charge cooler? I know they have been known to leak but I never heard of them leaking through to the air side… Maybe I'm wrong and others can chime in to confirm. As far as the sound and the loss of power, can you put a OBD tool on it to review the boost levels you're reaching? At least then you could confirm it's boost related and then there's only so many things it could be…

[AB M2C]

Charge cooler is full of coolant, i bled that early on in the process to try to figure this out, and it didn't take any. So i'm confident that is good. I'll try to log boost better, but might be a little difficult.

[AB M2C]

Any body have any other ideas? I don't have an easy way to take a boost log but my p3 guage is showing 21 psi. Which is maybe a little low but normal enough.

The noise is a fluttering sound.

Could it be the waste gates getting actuated somehow?

[NathObeaN]

Originally Posted by AB M2C

Any body have any other ideas? I don't have an easy way to take a boost log but my p3 guage is showing 21 psi. Which is maybe a little low but normal enough.

The noise is a fluttering sound.

Could it be the waste gates getting actuated somehow?

Do you have access to ISTA? It might be worth plugging it in to see if it picks up any issue (it will also provide diagnosis/troubleshooting steps). Is your tune hiding any error codes that would otherwise help identify the issue? Is it possible to flash to stock to help troubleshoot?

[AB M2C]

Originally Posted by NathObeaN

Do you have access to ISTA? It might be worth plugging it in to see if it picks up any issue (it will also provide diagnosis/troubleshooting steps). Is your tune hiding any error codes that would otherwise help identify the issue? Is it possible to flash to stock to help troubleshoot?

There aren't any codes being thrown. I've tried on the stock tune as well and the same issue is present and still no codes.

[hlm2c]

I would double check your connections to your air intake and also your charge pipes.. Could be a loose connection causing you to hear that whoosh when you mash on the gas pedal and air/boost is being sucked in.

[AB M2C]

Originally Posted by hlm2c

I would double check your connections to your air intake and also your charge pipes.. Could be a loose connection causing you to hear that whoosh when you mash on the gas pedal and air/boost is being sucked in.

I've checked that maybe 30 times and have fully replaced the plastic charge pipes. If there is a boost leak i'm certain its not to do with the charge pipe system.

[stefan]

Weird. My brother bought an f80 with the exact same phenomenon. I checked the inlet and didn't find any loose connections. I figured a vacuum or boost leak would trip a code but maybe not. I never ended up figuring it out. Keep us posted. Btw go back to stock tune.

[Track/S]

I don't understand very well what kind of sound the turbos are causing, check the wastegates are working, with the car stopped have someone accelerate and you see if the wastegate actuators move.

With the whoosh you mean this sound?
From 1:05

[AB M2C]

Originally Posted by stefan

Weird. My brother bought an f80 with the exact same phenomenon. I checked the inlet and didn't find any loose connections. I figured a vacuum or boost leak would trip a code but maybe not. I never ended up figuring it out. Keep us posted. Btw go back to stock tune.

Thats what I've been figuring too, but i've been through both systems so many times I feel that I've ruled them out. Still the issue persists. I've switched back to the stock tune. But its the same exact issue. And in kind of a funny way the car seems to make the same exact power on the stock tune as it does on the carbahn tune.

[AB M2C]

Originally Posted by Prodrive_X

I don't understand very well what kind of sound the turbos are causing, check the wastegates are working, with the car stopped have someone accelerate and you see if the wastegate actuators move.

With the whoosh you mean this sound?
From 1:05

So its not exactly that noise (its not compressor surge) But it is similar to that. Imagine the compressor surge noise but from 3-6k rpms repeating over and over. Thats the noise I'm hearing. I'll take the passenger intake off and have a look at the wastegates.

[robert58]

Blocked exhaust system.

[///MPECABL]

Originally Posted by robert58

Blocked exhaust system.

Could possibly be a blown out cat clogging the exhaust path… Good suggestion to take a look at the exhaust path. Seems like the front of the combustion process seems pretty well gone over.

[Track/S]

Originally Posted by ///MPECABL

Could possibly be a blown out cat clogging the exhaust path… Good suggestion to take a look at the exhaust path. Seems like the front of the combustion process seems pretty well gone over.

When there is an obstruction in the exhaust the sound decreases a lot, I ran into this problem, the turbo did not reach the required boost and with catless sounded less than originally with cat.

[AB M2C]

Originally Posted by Prodrive_X

When there is an obstruction in the exhaust the sound decreases a lot, I ran into this problem, the turbo did not reach the required boost and with catless sounded less than originally with cat.

Ohhh interesting. Thanks for the idea! I'll take a look.

[stefan]

Originally Posted by robert58

Blocked exhaust system.

I buy this. The stock cats are incredibly choking just to begin with. And like anything else they can fail. Normally you would get a weird smell with it too, its sort of sour, but then again that is on a mileaged out cat rather than one that maybe is abruptly clogged/failed.

[AB M2C]

Originally Posted by stefan

I buy this. The stock cats are incredibly choking just to begin with. And like anything else they can fail. Normally you would get a weird smell with it too, its sort of sour, but then again that is on a mileaged out cat rather than one that maybe is abruptly clogged/failed.

Ya thats my one concern as well. Its interesting that it would be a sudden issue. Also would be strange to have blocked cats and no CEL. car only has 22k miles on it.

Having said that I ordered some downpipes so we'll see what happens.

[turnsignalslol]

Originally Posted by AB M2C

Ya thats my one concern as well. Its interesting that it would be a sudden issue. Also would be strange to have blocked cats and no CEL. car only has 22k miles on it.

Having said that I ordered some downpipes so we'll see what happens.

It would really help to try and get some audio of the issue you're talking about. Just try and record it so that we can get a better idea of what you're talking about.

Keep us updated!