N55 Diverter Valve

Pladi · 12-19-2018, 09:56 AM

Has anyone replaced this part or upgraded. I wanted to know how hard is to replace and what was the reason for replacing.

Also do OEM ones fail often ?

weehe126 · 12-19-2018, 11:16 AM

It is difficult to replace as it is very tight. Most people have to remove the water pump/thermostat to get to it. Some say you can get to it from the top by removing both turbo inlet/outlet pipes. Upgrade option is the Go Fast Bits DV. I've only seen people replace them as a last resort due to unknown boost leak/high WGDC. I replaced mine when I went PS2 and the GFB dv was hard enough to bolt on with the turbo out. Can't imagine with turbo in place.

Pladi · 12-19-2018, 01:00 PM

Quote:

Originally Posted by weehe126

It is difficult to replace as it is very tight. Most people have to remove the water pump/thermostat to get to it. Some say you can get to it from the top by removing both turbo inlet/outlet pipes. Upgrade option is the Go Fast Bits DV. I've only seen people replace them as a last resort due to unknown boost leak/high WGDC. I replaced mine when I went PS2 and the GFB dv was hard enough to bolt on with the turbo out. Can't imagine with turbo in place.

makes sense. Did you notice any improvements ? Some after market manufactures promise it eliminates boost spikes during gear shift under WOT.

Are you hitting targets better ?

weehe126 · 12-19-2018, 01:09 PM

There was no issue with my stock dv at 98k miles. I just did it as insurance since I was swapping the turbo. I doubt it would effect boost spikes with gear shifts. The only thing I could see it help is possibly prevent a boost leak.

Pladi · 12-19-2018, 01:30 PM

Quote:

Originally Posted by weehe126

There was no issue with my stock dv at 98k miles. I just did it as insurance since I was swapping the turbo. I doubt it would effect boost spikes with gear shifts. The only thing I could see it help is possibly prevent a boost leak.

makes sense thanks.

Aseneph · 12-19-2018, 01:34 PM

I installed the GFB DV+ myself in a couple hours. Isn't too hard, just a pain to get to. I haven't upgraded turbo yet or nothing. Just remove water pump and loosen tstat to slide over. No huge difference. Just holds boost better and eases my mind.

Turbod · 12-19-2018, 01:35 PM

As stated it is difficult to replace when the turbofold is still installed on the car. The issue with installing it when the turbo is out is that the larger housing of the DV+ block one of the coolant line bolts. I only installed it because it was recommended with the PS2. I would have only done the swap on the stock turbo if I felt that it was leaking boost.

cahme · 12-19-2018, 02:12 PM

Mine failed at about 120k mi
Pics and my install comments are in this thread:
https://www.e90post.com/forums/showthread.php?t=1289466

Pladi · 12-19-2018, 02:36 PM

Ok seems like if i do the water pump then i might replace it as preventative.

I am not able to hit targets boost for about 2 PSI for the entire pull. This is also with stage 1 so i am looking at options and leak areas. I will be replacing a solenoid valve soon and was gonna do this but too much work for some boost loss might wait until i have more repairs needed.

Pladi · 12-19-2018, 03:26 PM

Quote:

Originally Posted by cahme

Mine failed at about 120k mi
Pics and my install comments are in this thread:
https://www.e90post.com/forums/showthread.php?t=1289466

Oh man your almost changing my mind amazing post. How did i miss that.

Thats exactly the type of info i was looking for.

Pladi · 12-19-2018, 03:29 PM

Quote:

Originally Posted by cahme

Mine failed at about 120k mi
Pics and my install comments are in this thread:
https://www.e90post.com/forums/showthread.php?t=1289466

do you happen to have logs of that time ?

fatty335 · 12-19-2018, 07:24 PM

Pladi,

I replced mine @65K miles after loading a tune with a higher peak boost that the stock valve was unable to deal with. It kept audibly dumping boost right after spool and consistantly ran 2 - 3 psi short of target. After chasing a boost leak that didn't exist, I installed the GFB and haven't had an issue since. Also, you can install it without removing/draining the water pump. You will need to loosen it to gain access to the third allen-head bolt though, and go in from the front (radiator fan removed). Good luck.

Pladi · 12-19-2018, 07:36 PM

Quote:

Originally Posted by fatty335

Pladi,

I replced mine @65K miles after loading a tune with a higher peak boost that the stock valve was unable to deal with. It kept audibly dumping boost right after spool and consistantly ran 2 - 3 psi short of target. After chasing a boost leak that didn't exist, I installed the GFB and haven't had an issue since. Also, you can install it without removing/draining the water pump. You will need to loosen it to gain access to the third allen-head bolt though, and go in from the front (radiator fan removed). Good luck.

Thank you sir ! Very good advice.

cahme · 12-20-2018, 07:41 AM

Quote:

Originally Posted by Pladi

do you happen to have logs of that time ?

I was able to find a Map1 and Map4 log around when the issue started.
https://datazap.me/u/cahme00/e90-jb4-map-1?log=0&data=1-3-4
https://datazap.me/u/cahme00/e90-jb4-map-4?log=0&data=1-3-4

OP3NAIR · 12-20-2018, 01:33 PM

I put a DV+ in when my waterpump went out. With the water pump out, its not that hard to get to it. You need an allen key for a socket wrench thats about 5" long and you can easily work the bolts in and out of the turbo housing.

12-19-2018, 09:56 AM	#1
Pladi Lieutenant Colonel 718 Rep 1,753 Posts Drives: 2011 335i xdrive Join Date: Nov 2017 Location: Waterloo, ON Canada iTrader: (0)	N55 Diverter Valve Has anyone replaced this part or upgraded. I wanted to know how hard is to replace and what was the reason for replacing. Also do OEM ones fail often ?
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12-19-2018, 11:16 AM	#2
weehe126 Brigadier General 1161 Rep 3,189 Posts Drives: 2017 340i Join Date: Apr 2014 Location: San Antonio iTrader: (2)	It is difficult to replace as it is very tight. Most people have to remove the water pump/thermostat to get to it. Some say you can get to it from the top by removing both turbo inlet/outlet pipes. Upgrade option is the Go Fast Bits DV. I've only seen people replace them as a last resort due to unknown boost leak/high WGDC. I replaced mine when I went PS2 and the GFB dv was hard enough to bolt on with the turbo out. Can't imagine with turbo in place.
	Appreciate 2 Pladi718.00 Turbod395.50 Quote

12-19-2018, 01:09 PM	#4
weehe126 Brigadier General 1161 Rep 3,189 Posts Drives: 2017 340i Join Date: Apr 2014 Location: San Antonio iTrader: (2)	There was no issue with my stock dv at 98k miles. I just did it as insurance since I was swapping the turbo. I doubt it would effect boost spikes with gear shifts. The only thing I could see it help is possibly prevent a boost leak.
	Appreciate 1 Turbod395.50 Quote

12-19-2018, 01:34 PM	#6
Aseneph Private First Class 37 Rep 134 Posts Drives: 2012 BMW 335i Coupe Join Date: Dec 2016 Location: Tulsa, Ok iTrader: (0)	I installed the GFB DV+ myself in a couple hours. Isn't too hard, just a pain to get to. I haven't upgraded turbo yet or nothing. Just remove water pump and loosen tstat to slide over. No huge difference. Just holds boost better and eases my mind.
	Appreciate 1 Pladi718.00 Quote

12-19-2018, 01:35 PM	#7
Turbod Major 396 Rep 1,210 Posts Drives: 2014 E84 X1 35i M Sport Join Date: Mar 2015 Location: Oregon iTrader: (0)	As stated it is difficult to replace when the turbofold is still installed on the car. The issue with installing it when the turbo is out is that the larger housing of the DV+ block one of the coolant line bolts. I only installed it because it was recommended with the PS2. I would have only done the swap on the stock turbo if I felt that it was leaking boost. __________________ 2011 E92 335i \| 11.7@125 SOLD 2017 Camaro SS \| 12.7@114 SOLD 2019 Audi TT RS \| 10.5@130 SOLD 2020 F97 X3M \| 11.0@123 2023 G80 M3 xDrive
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12-19-2018, 02:12 PM	#8
cahme Second Lieutenant 116 Rep 226 Posts Drives: '11 E90 335i Sport MT Join Date: Jul 2015 Location: Texas iTrader: (0)	Mine failed at about 120k mi Pics and my install comments are in this thread: https://www.e90post.com/forums/showthread.php?t=1289466
	Appreciate 1 Pladi718.00 Quote

12-19-2018, 02:36 PM	#9
Pladi Lieutenant Colonel 718 Rep 1,753 Posts Drives: 2011 335i xdrive Join Date: Nov 2017 Location: Waterloo, ON Canada iTrader: (0)	Ok seems like if i do the water pump then i might replace it as preventative. I am not able to hit targets boost for about 2 PSI for the entire pull. This is also with stage 1 so i am looking at options and leak areas. I will be replacing a solenoid valve soon and was gonna do this but too much work for some boost loss might wait until i have more repairs needed.
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12-19-2018, 07:24 PM	#12
fatty335 Private First Class 123 Rep 109 Posts Drives: e90 335i Join Date: Apr 2018 Location: The Palmetto State iTrader: (0)	Pladi, I replced mine @65K miles after loading a tune with a higher peak boost that the stock valve was unable to deal with. It kept audibly dumping boost right after spool and consistantly ran 2 - 3 psi short of target. After chasing a boost leak that didn't exist, I installed the GFB and haven't had an issue since. Also, you can install it without removing/draining the water pump. You will need to loosen it to gain access to the third allen-head bolt though, and go in from the front (radiator fan removed). Good luck.
	Appreciate 1 Pladi718.00 Quote

12-20-2018, 01:33 PM	#15
OP3NAIR Second Lieutenant 68 Rep 211 Posts Drives: '11 335i e93, '03 325xiT Join Date: Jan 2015 Location: NoVA iTrader: (0)	I put a DV+ in when my waterpump went out. With the water pump out, its not that hard to get to it. You need an allen key for a socket wrench thats about 5" long and you can easily work the bolts in and out of the turbo housing.
	Appreciate 1 Pladi718.00 Quote