Siren Noise Coming from Turbos

TiAg335i · 12-20-2009, 03:31 PM

When the engine is cold, and at low RPM's, I have this howl, low siren type of noise coming from the engine. It goes away after 3 minutes of driving.

I have JB+ at 100% and used to have DCI. Pretty much everyone on this forum has told me that this means the turbos are failing, but no one has had any evidence to prove it.

My car is running stronger than ever, if my turbos were failing wouldn't I suffer some kind of power loss? What should I do? Please, no speculation.

e.n335 · 12-20-2009, 03:38 PM

Quote:

Originally Posted by TiAg335i

When the engine is cold, and at low RPM's, I have this howl, low siren type of noise coming from the engine. It goes away after 3 minutes of driving ...

In case the noise disappears when the oil gets warm and it does not sound that loud you can drive forever

. I had this on my first turbo-set for more than 30K miles. Then they have been replaced due to wategate rattle.

In case the noise is there all of the time it will get just louder and the turbos wear out, IMO.

Cheers,
Eugen

TiAg335i · 12-20-2009, 03:41 PM

Quote:

Originally Posted by e.n335

In case the noise disappears when the oil gets warm and it does not sound that loud you can drive forever

. I had this on my first turbo-set for more than 30K miles. Then they have been replaced due to wategate rattle.

In case the noise is there all of the time it will get just louder and the turbos wear out, IMO.

Cheers,
Eugen

Ok, so there is nothing physically wrong with the turbos then?

Terrance28 · 12-20-2009, 03:44 PM

I have that noise. I can only hear it when the oil is cold and from 1500-2000rpms. I took it to the dealer and they said it is normal, when turbos start to fail or fail trust me you will know.

e.n335 · 12-20-2009, 03:44 PM

Quote:

Originally Posted by TiAg335i

Ok, so there is nothing physically wrong with the turbos then?

There is something wrong but it will not impact anything as long as the sound is quite silent and goes away when the engine gets warm.

TiAg335i · 12-20-2009, 03:48 PM

Quote:

Originally Posted by e.n335

There is something wrong but it will not impact anything as long as the sound is quite silent and goes away when the engine gets warm.

If there is something wrong, I should get it fixed and not keeping driving it then, no?

e.n335 · 12-20-2009, 03:53 PM

Quote:

Originally Posted by TiAg335i

If there is something wrong, I should get it fixed and not keeping driving it then, no?

BMW will not accept this as an issue. I once got a brand-new X5 3.0d making this turbo noise. Did 40K miles with the X5, no issues. My current turbos on the 335i make no noise at all. Your issue - worth to repair ? No, IMO.

TiAg335i · 12-20-2009, 03:56 PM

Quote:

Originally Posted by e.n335

BMW will not accept this as an issue. I once got a brand-new X5 3.0d making this turbo noise. Did 40K miles with the X5, no issues. My current turbos on the 335i make no noise at all. Your issue - worth to repair ? No, IMO.

Do you think the JB+ or my driving style may be exacerbating the issue?

e.n335 · 12-20-2009, 03:58 PM

Quote:

Originally Posted by TiAg335i

Do you think the JB+ or my driving style may be exacerbating the issue?

Bomis · 12-20-2009, 04:12 PM

I had my both turbos replaced two months ago and even i have that problem when the car is cold with the new turbos, and its winter here and im on map 0 so i haven't even overboost my turbos...so i would not be that worried....

TiAg335i · 12-20-2009, 04:17 PM

Thanks guys. I guess I don't have much to worry about if it happens even with new turbos.

e.n335 · 12-20-2009, 04:26 PM

The Alpina B3 Twin Turbo boosts 16 psi with those turbos stock. So the turbos should work @ 16 psi for BMW's as well

. The danger seems to be to run them over 12 psi at >= 6000 rpm, here they seem to run out of their efficiency range and start to overspool ( > 200.000 rpm ). However, still depending on the parasitic loss of the entire boost system.

GAaaAR · 12-20-2009, 06:12 PM

I have this issue as well although not that loud and only happens when its cold. I think the only issue is the noise itself, performance or as far as turbo lifespan should be the same. I just ignore it now.

cn555ic · 12-20-2009, 07:35 PM

I think its safe to say that this noise is probably normal during cold starts because so many people are experiencing this and with the noise going away after the engine warms.....

12-20-2009, 03:31 PM	#1
TiAg335i Trance Life 315 Rep 4,706 Posts Drives: 2007 E92 335i Join Date: Jan 2007 Location: Long Island, NY iTrader: (4)	Siren Noise Coming from Turbos When the engine is cold, and at low RPM's, I have this howl, low siren type of noise coming from the engine. It goes away after 3 minutes of driving. I have JB+ at 100% and used to have DCI. Pretty much everyone on this forum has told me that this means the turbos are failing, but no one has had any evidence to prove it. My car is running stronger than ever, if my turbos were failing wouldn't I suffer some kind of power loss? What should I do? Please, no speculation.
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12-20-2009, 03:44 PM	#4
Terrance28 Brigadier General 109 Rep 3,334 Posts Drives: Crimson Red E92 Join Date: Nov 2007 Location: Killeen, TX iTrader: (17)	I have that noise. I can only hear it when the oil is cold and from 1500-2000rpms. I took it to the dealer and they said it is normal, when turbos start to fail or fail trust me you will know. __________________ Mods list got too long, lets just say more than enough.
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12-20-2009, 04:12 PM	#10
Bomis Captain 63 Rep 989 Posts Drives: BMW E92 M3 Join Date: Apr 2009 Location: Sweden iTrader: (1)	I had my both turbos replaced two months ago and even i have that problem when the car is cold with the new turbos, and its winter here and im on map 0 so i haven't even overboost my turbos...so i would not be that worried.... __________________ EURO E92 M3 2008 6MT Interlagos ///*Fully Loaded!* Evolve-R ECU Flash/Gintani Sport Exhaust/MS Stg2 Intake Kit/H&R Springs/MS 18/15 mm spacers/Bmw Perf. Grills/Gloss Black side gills/LCI Tails/LUX V3's/RD license plate leds
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12-20-2009, 04:17 PM	#11
TiAg335i Trance Life 315 Rep 4,706 Posts Drives: 2007 E92 335i Join Date: Jan 2007 Location: Long Island, NY iTrader: (4)	Thanks guys. I guess I don't have much to worry about if it happens even with new turbos.
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12-20-2009, 04:26 PM	#12
e.n335 Moderator 270 Rep 4,481 Posts Drives: e93 ///M3 DCT, 07/2009 Join Date: Feb 2007 Location: Switzerland, ZH iTrader: (0)	The Alpina B3 Twin Turbo boosts 16 psi with those turbos stock. So the turbos should work @ 16 psi for BMW's as well . The danger seems to be to run them over 12 psi at >= 6000 rpm, here they seem to run out of their efficiency range and start to overspool ( > 200.000 rpm ). However, still depending on the parasitic loss of the entire boost system.
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12-20-2009, 06:12 PM	#13
GAaaAR Captain 33 Rep 671 Posts Drives: 2009 E92 335i Join Date: May 2006 Location: NYC iTrader: (1)	I have this issue as well although not that loud and only happens when its cold. I think the only issue is the noise itself, performance or as far as turbo lifespan should be the same. I just ignore it now.
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12-20-2009, 07:35 PM	#14
cn555ic 441 Rep 18,331 Posts Drives: 335i Join Date: Jun 2007 Location: US iTrader: (6)	I think its safe to say that this noise is probably normal during cold starts because so many people are experiencing this and with the noise going away after the engine warms.....
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