How to find out if you have a small boost leak in the DV's?

E90Company · 07-15-2012, 11:08 PM

Hello guys,

I think I may have a minor boost leak in the stock DV's. I am not throwing any codes, but the car is choppy at half throttle around 10psi with the JB4, and when I let off the throttle quickly I hear a wierd sound which sounds like it is coming from the DV's, almost a vacuum sound. I have never boosted higher than map 1. Is there a way to tell easily? What should I do? I heard smoke testing being thrown around but I don't think this is for the DV's?

Any help is appreciated. Thanks. I am under CPO as well, could I get them replaced inder warranty even though no codes are being thrown?

EDIT: Forgot to add, I am JB4 and DCI only ever run on map 1. When I was stock, I noticed a turbo whine sound while under low RPM boost which I thought was normal, but now it has me questioning wether they were leaking before I was even tuned. I still here it now, but the DCI really masks the sound

E90Company · 07-16-2012, 12:30 AM

Bump.

secretsquirrel · 07-16-2012, 07:19 AM

Have someone rev your car and you spray a light solution of water and dish soap on them and see if they bubble?

benzy89 · 07-16-2012, 08:23 AM

This is your 2nd thread about the same problem. Like squirrel said, get a spray bottle & get some water on the various connections. If bubble come out, there's your leak.

Also recommend looking for obvious cracks in your CP, specifically on the throttle body connection

Tzu · 07-16-2012, 09:28 AM

You won't build enoguh boost revving in neutral. Suggest popping off the hot side IC connection and pressurizing with shop air to 15psi, then spray.

nitehawk · 07-16-2012, 09:55 AM

Log data. Your boost profile and WGDC should tell the truth.

Mike@N54Tuning.com · 07-16-2012, 09:59 AM

Quote:

Originally Posted by nitehawk

Log data. Your boost profile and WGDC should tell the truth.

+1

Shoot a CSV log over to either myself or Terry.

Mike

E90Company · 07-16-2012, 10:09 AM

Quote:

Originally Posted by Mike@N54Tuning.com

+1

Shoot a CSV log over to either myself or Terry.

Mike

Sounds good. Thanks.

J Boy · 07-16-2012, 12:46 PM

push the diaphragm up from the bottom and then plug the vacuum hole with your finger and the diaphragm should stay in the same position until you move your finger.. if not then it's leaking

Slops · 07-16-2012, 01:59 PM

I'm not sure bout the TT but when I had my srt-4 it was pretty easy to test for boost leaks. You can buy a boost leak tester or make one yourself. What you do is take the intake off and hook the tester up on the intake side of the turbo. Then you close any other connections off that are sensors etc as they'll just blow out. Then pump Ty system up to 20psi with a normal compressor and spray your connections with soapy water.... Soap = easy bubbles

hope that helps...

07-15-2012, 11:08 PM	#1
E90Company Major General 195 Rep 6,136 Posts Drives: Car Join Date: Mar 2012 Location: FL iTrader: (2)	How to find out if you have a small boost leak in the DV's? Hello guys, I think I may have a minor boost leak in the stock DV's. I am not throwing any codes, but the car is choppy at half throttle around 10psi with the JB4, and when I let off the throttle quickly I hear a wierd sound which sounds like it is coming from the DV's, almost a vacuum sound. I have never boosted higher than map 1. Is there a way to tell easily? What should I do? I heard smoke testing being thrown around but I don't think this is for the DV's? Any help is appreciated. Thanks. I am under CPO as well, could I get them replaced inder warranty even though no codes are being thrown? EDIT: Forgot to add, I am JB4 and DCI only ever run on map 1. When I was stock, I noticed a turbo whine sound while under low RPM boost which I thought was normal, but now it has me questioning wether they were leaking before I was even tuned. I still here it now, but the DCI really masks the sound
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07-16-2012, 12:30 AM	#2
E90Company Major General 195 Rep 6,136 Posts Drives: Car Join Date: Mar 2012 Location: FL iTrader: (2)	Bump.
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07-16-2012, 07:19 AM	#3
secretsquirrel Colonel 130 Rep 2,291 Posts Drives: f80 Join Date: Dec 2010 Location: Far North Dallas iTrader: (2)	Have someone rev your car and you spray a light solution of water and dish soap on them and see if they bubble?
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07-16-2012, 08:23 AM	#4
benzy89 Banned 79 Rep 2,396 Posts Drives: '08 E90 335i Join Date: Jan 2012 Location: Northern NJ iTrader: (3) Garage List 2008 BMW 335i [7.50]	This is your 2nd thread about the same problem. Like squirrel said, get a spray bottle & get some water on the various connections. If bubble come out, there's your leak. Also recommend looking for obvious cracks in your CP, specifically on the throttle body connection
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07-16-2012, 09:28 AM	#5
Tzu Lieutenant Colonel 29 Rep 1,551 Posts Drives: 335i Join Date: Jun 2010 Location: Toronto iTrader: (1)	You won't build enoguh boost revving in neutral. Suggest popping off the hot side IC connection and pressurizing with shop air to 15psi, then spray.
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07-16-2012, 09:55 AM	#6
nitehawk Lieutenant Colonel 102 Rep 1,903 Posts Drives: e92 335i 6MT Join Date: May 2011 Location: Toronto iTrader: (15) Garage List E92 BMW 335i [9.00] E92 BMW 335i \| Retired [10.00]	Log data. Your boost profile and WGDC should tell the truth.
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07-16-2012, 12:46 PM	#9
J Boy Private 0 Rep 68 Posts Drives: B6 A4 Join Date: Jun 2012 Location: West Covina iTrader: (0)	push the diaphragm up from the bottom and then plug the vacuum hole with your finger and the diaphragm should stay in the same position until you move your finger.. if not then it's leaking __________________ B6 A4 REVO Stage 2
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07-16-2012, 01:59 PM	#10
Slops Major General 188 Rep 5,417 Posts Drives: 2005 C55 AMG Join Date: Jan 2011 Location: Oxford iTrader: (2)	I'm not sure bout the TT but when I had my srt-4 it was pretty easy to test for boost leaks. You can buy a boost leak tester or make one yourself. What you do is take the intake off and hook the tester up on the intake side of the turbo. Then you close any other connections off that are sensors etc as they'll just blow out. Then pump Ty system up to 20psi with a normal compressor and spray your connections with soapy water.... Soap = easy bubbles hope that helps...
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