Squealing noise under boost

motoguat · 09-10-2019, 01:00 AM

Anyone ever experience a pretty loud squealing noise under boost?

The other day, I took the car out for a quick run after putting new battery in it. Once it was warmed up, I pushed it and saw a spike in boost then when I turned around to head home, heard some pretty loud squealing that coincided with boost.

-No Loss of boost
-new batter
-car is fully deleted and has DUDMD tune (stg 2)

Here is the video, kind of hard to hear because its recorded using my phone.

Thanks!

RL18 · 09-10-2019, 09:49 AM

Sounds like a belt or pulley to me

Theana9 · 09-10-2019, 09:58 AM

Nice

PerfectAce · 09-10-2019, 10:20 AM

Hard to really hear the "squeal" clearly on the video, but if it is a squeal as you say, then it may very well be your crank pulley (harmonic dampener) on it's last leg. With the engine at idle, the rubber may be just holding together, but any increased engine speed causes the rubber to shear and belt(s) to slip.

Park the car, open the hood, and observe the belt movement as the engine is revved. If you're able to reproduce the sound and if the pulley is the issue, you'll see the belt moving intermittently.

Could also be a loose A/C belt that is only slipping at engine speeds >idle . Try the same observations with the A/C turned off and see if that makes a difference.

PerfectAce · 09-10-2019, 10:25 AM

Also, just out of curiosity, did you replace the battery because the car was signalling a low battery voltage warning? If so, this is more evidence that your crank pulley has failed. (Pulley failed -> belts don't move -> alternator don't spin -> battery don't charge.)

motoguat · 09-11-2019, 08:32 AM

Thanks PerfectAce, good advice for me to check that. I got in there yesterday and looks like its not a pulley issue.

I replaced the batter because I was getting slow cranks, low battery voltage warning and I was monitoring voltage using the secret menu on dash.

I started the motor yesterday and let it run for a few minutes to check and top off oil but discovered that it was low by 2 quarts!! I had never got a low oil indication warning so I am not sure how long ive been driving around with that low of oil.

I am taking the car into a shop today but I hate taking my cars to shops, however, I am stumped right now and sort of out of my element with this M57 motor. I will update once I hear back from them and hopefully I dont have catastrophic damages to the motor.

DG330 · 09-12-2019, 04:10 PM

Keen to see what this is. Could it be turbo? Any smoke? Power loss?

motoguat · 09-13-2019, 11:21 AM

I heard back from the shop and unfortunately, they didnt get too far. They ran some smoke through the system for starters and found that the CCV tube is very faulty.

I cant imagine that being the issue but I ordered the replacement part and will be fixing this on my own as the shop quoted me a little over 500 for the parts and labor.

motoguat · 09-16-2019, 11:58 AM

Quote:

Originally Posted by Txs330D

Keen to see what this is. Could it be turbo? Any smoke? Power loss?

Shop looked at the car and concluded that they need to have the CCV tube replaced before being able to continue their test.

No smoke or power loss at the moment.

09-10-2019, 01:00 AM	#1
motoguat New Member 1 Rep 6 Posts Drives: 2006 330i Join Date: Jun 2018 Location: Beaverton, OR iTrader: (0)	Squealing noise under boost Anyone ever experience a pretty loud squealing noise under boost? The other day, I took the car out for a quick run after putting new battery in it. Once it was warmed up, I pushed it and saw a spike in boost then when I turned around to head home, heard some pretty loud squealing that coincided with boost. -No Loss of boost -new batter -car is fully deleted and has DUDMD tune (stg 2) Here is the video, kind of hard to hear because its recorded using my phone. Thanks!
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09-10-2019, 09:49 AM	#2
RL18 Major 274 Rep 1,054 Posts Drives: 2011 335d sport Join Date: Nov 2017 Location: Maine iTrader: (0)	Sounds like a belt or pulley to me __________________ 2011 335d tuned by B.R.R. 2011 X5 35d tuned by B.R.R.
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09-10-2019, 09:58 AM	#3
Theana9 Banned 2 Rep 15 Posts Drives: E90 Join Date: Aug 2019 Location: Jakarta iTrader: (0)	Nice
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09-10-2019, 10:20 AM	#4
PerfectAce Second Lieutenant 107 Rep 202 Posts Drives: 2011 335d Sport Join Date: Jun 2017 Location: Austin, Texas iTrader: (0)	Hard to really hear the "squeal" clearly on the video, but if it is a squeal as you say, then it may very well be your crank pulley (harmonic dampener) on it's last leg. With the engine at idle, the rubber may be just holding together, but any increased engine speed causes the rubber to shear and belt(s) to slip. Park the car, open the hood, and observe the belt movement as the engine is revved. If you're able to reproduce the sound and if the pulley is the issue, you'll see the belt moving intermittently. Could also be a loose A/C belt that is only slipping at engine speeds >idle . Try the same observations with the A/C turned off and see if that makes a difference.
	Appreciate 0 Quote

09-10-2019, 10:25 AM	#5
PerfectAce Second Lieutenant 107 Rep 202 Posts Drives: 2011 335d Sport Join Date: Jun 2017 Location: Austin, Texas iTrader: (0)	Also, just out of curiosity, did you replace the battery because the car was signalling a low battery voltage warning? If so, this is more evidence that your crank pulley has failed. (Pulley failed -> belts don't move -> alternator don't spin -> battery don't charge.)
	Appreciate 0 Quote

09-11-2019, 08:32 AM	#6
motoguat New Member 1 Rep 6 Posts Drives: 2006 330i Join Date: Jun 2018 Location: Beaverton, OR iTrader: (0)	Thanks PerfectAce, good advice for me to check that. I got in there yesterday and looks like its not a pulley issue. I replaced the batter because I was getting slow cranks, low battery voltage warning and I was monitoring voltage using the secret menu on dash. I started the motor yesterday and let it run for a few minutes to check and top off oil but discovered that it was low by 2 quarts!! I had never got a low oil indication warning so I am not sure how long ive been driving around with that low of oil. I am taking the car into a shop today but I hate taking my cars to shops, however, I am stumped right now and sort of out of my element with this M57 motor. I will update once I hear back from them and hopefully I dont have catastrophic damages to the motor.
	Appreciate 0 Quote

09-12-2019, 04:10 PM	#7
DG330 First Lieutenant 70 Rep 360 Posts Drives: 330 Join Date: Nov 2018 Location: Uk iTrader: (0)	Keen to see what this is. Could it be turbo? Any smoke? Power loss?
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09-13-2019, 11:21 AM	#8
motoguat New Member 1 Rep 6 Posts Drives: 2006 330i Join Date: Jun 2018 Location: Beaverton, OR iTrader: (0)	I heard back from the shop and unfortunately, they didnt get too far. They ran some smoke through the system for starters and found that the CCV tube is very faulty. I cant imagine that being the issue but I ordered the replacement part and will be fixing this on my own as the shop quoted me a little over 500 for the parts and labor.
	Appreciate 0 Quote