N55 Low Boost Cont'd

n55problemdude · 10-23-2017, 08:56 AM

Hello Guys,

My N55 has had low boost issues for a little over a month now. Changed charge pipe (was cracked), got jb4, intake, down pipes, did oil gasket leak, changed vent hose. Did diagnosis by BMW which they told me to fix my CP, vent hose, and oil gasket. Did smoke test and general diagnosis by Petrol Werks, no problems seen except code: *BLOW OFF VALVE JAMMED*. Thing is, N55 has a diverter valve so I'm guessing the code is talking about that. They said if I change the DV and nothing helps, then I need to change the turbo. I NEED HELP BECAUSE I DONT WANNA WASTE ANY MORE MONEY ON BS AND HAVE THE CAR STILL LOW BOOSTING. I am able to hear the boost while in the car so it's still spooling. I've noticed little rattling when starting up the car in the morning (cold starts). Also once in a while I hear rattling out the exhausts in the back for about a minute and then it stops. Once I replaced charge pipe, I wasn't getting any reduced power or check engine lights. When I plugged in JB4, I am still low boosting, but now I'm getting reduced engine warnings after like 3-4k rpms but car is still not limp mode! JB4 reads 1-4 psi on average, when I upshift it jumps like 3-4 psi. Any help would be greatly appreciated!! Thanks

weehe126 · 10-23-2017, 10:13 AM

FFS stop making new threads and post a damn log. If you are only having this issue with the JB4 you probably have the wrong firmware loaded.

n55problemdude · 10-23-2017, 11:01 AM

Quote:

Originally Posted by weehe126

FFS stop making new threads and post a damn log. If you are only having this issue with the JB4 you probably have the wrong firmware loaded.

idk what you mean by making a log. I'm new to this posting shit. It's not a fault w the jb4 because I already updated it and it works fine. I'm just mad desperate for a solution man. Sorry that its such of a trouble for you to see one extra post that I made to get some more responses and more input from myself. I'll be sure to cater to what you want now.

weehe126 · 10-23-2017, 12:12 PM

The reason you don't make multiple posts on the same issue is so people can actually follow the progression. It's not my preference, it's everyone's and helps you get help.

How do you know you are only getting 1-3 psi? Guessing? In dash gauge? Logging with your computer or phone?

How do you know the JB4 is working fine if you are only getting 1-3psi? Was the JB4 installed every time you brought it to the shop? Does it only have 1-3psi with the JB4 removed, how have you checked?

This isn't rocket science. It can only be mechanical (boost leak, leaking DV, stuck open wastegate, bad boost solenoid, bad turbo) or electrical (wrong JB4 firmware, or something is unplugged). Go down the list and check things off.

You are in college and have a car that drives, stop bitching like it's the end of the world.

nissubaru · 10-23-2017, 01:28 PM

Quote:

Originally Posted by n55problemdude

idk what you mean by making a log. I'm new to this posting shit. It's not a fault w the jb4 because I already updated it and it works fine. I'm just mad desperate for a solution man. Sorry that its such of a trouble for you to see one extra post that I made to get some more responses and more input from myself. I'll be sure to cater to what you want now.

You need the serial to USB cable available for the JB4. It doesn't come with it for free so you would have needed to purchase it, however it sounds like you have it? If you have it then open up the JB4 program and make a log using the screen shown below:

Idk what this will tell us specifically aside from confirming you aren't hitting your boost targets and maybe your AFRs are fucky, but I'm not much of a tuner.

Supposedly "2C90: Blow-off valve, mechanics: Jammed closed" is a bullshit code on the N55 and it just gets thrown randomly when the cars are tuned.

http://www.e90post.com/forums/showthread.php?t=790312

How true this is, I'm not sure. I'd try clearing the codes and see if they come back.

n55problemdude · 10-23-2017, 01:39 PM

Quote:

Originally Posted by weehe126

The reason you don't make multiple posts on the same issue is so people can actually follow the progression. It's not my preference, it's everyone's and helps you get help.

How do you know you are only getting 1-3 psi? Guessing? In dash gauge? Logging with your computer or phone?

How do you know the JB4 is working fine if you are only getting 1-3psi? Was the JB4 installed every time you brought it to the shop? Does it only have 1-3psi with the JB4 removed, how have you checked?

This isn't rocket science. It can only be mechanical (boost leak, leaking DV, stuck open wastegate, bad boost solenoid, bad turbo) or electrical (wrong JB4 firmware, or something is unplugged). Go down the list and check things off.

You are in college and have a car that drives, stop bitching like it's the end of the world.

Sorry youre right bro. I'm just really frustrated about it already and want it to drive like its supposed to. JB4 is showing 1-4 on avg with a spike of like 3-4 psi when shifting up, on the fuel gauge. Jb4 is working properly because all the options and settings work. Plus the car was under boosting prior to me putting on the JB4, triple checked installation. Changed boost solenoid, got a smoke test. People saying it sounds like wastegate could be stuck open. Any idea how I can get to it the easiest on an n55?

weehe126 · 10-23-2017, 01:53 PM

You have to answer the rest of my questions for anyone to be able to help.

How do you know it is only boosting 1-4psi with JB4 off?
Was the JB4 installed when all of the shops looked at it?

Unless the DV literally fell out, I doubt the DV is the issue. There is no easy way to verify it's function unless you know what you are looking for.

What options and settings are you talking about. You can have the wrong firmware and all the steering wheel/dash stuff will work fine. I have literally uploaded the wrong firmware before and got 1-4psi just like you are saying.

Go buy the cable from BMS and post a screen shot of your user adjustments tab as shown above.

n55problemdude · 10-23-2017, 05:02 PM

The car was producing equal power with JB4 off and now with it on I can see that it is only producing 1-4 psi on average. JB4 was only installed when petrol werks took a look at it, and they toggled through it to make sure it works. (One of the first things they looked at) I updated the firmware with the usb once I got it, twice, to make sure its compatible with my car settings and etc. People are saying check my waste gate to see if its stuck. I'll try that. Thanks for the help. If you have any additional things you think I should look at or do, please feel free to tell. Thanks again.

BimmerNugget · 10-23-2017, 05:24 PM

Stop Posting This S**t So Many Goddamn Times! I Swear This Is Like The 4th Thread You've Started On Your Damn Problem. I Will Legit Go To Bing U And Beat You Until You Turn Purple If You Post This Crap One More Time.

Stop Being A Cheap Bastard And Get A Proper Bmw Scanner ($140 For Foxwell Nt510) Or Just Take Your Car To An Indy Mechanic.

n55problemdude · 10-23-2017, 05:56 PM

Quote:

Originally Posted by BimmerNugget

Stop Posting This S**t So Many Goddamn Times! I Swear This Is Like The 4th Thread You've Started On Your Damn Problem. I Will Legit Go To Bing U And Beat You Until You Turn Purple If You Post This Crap One More Time.

Stop Being A Cheap Bastard And Get A Proper Bmw Scanner ($140 For Foxwell Nt510) Or Just Take Your Car To An Indy Mechanic.

328 drivers stay mad

weehe126 · 10-23-2017, 06:00 PM

Quote:

Originally Posted by n55problemdude

The car was producing equal power with JB4 off and now with it on I can see that it is only producing 1-4 psi on average. JB4 was only installed when petrol werks took a look at it, and they toggled through it to make sure it works. (One of the first things they looked at) I updated the firmware with the usb once I got it, twice, to make sure its compatible with my car settings and etc. People are saying check my waste gate to see if its stuck. I'll try that. Thanks for the help. If you have any additional things you think I should look at or do, please feel free to tell. Thanks again.

If you have the cable then you can log. Go to N54 tech and read up on logging. Post a picture of your user adjustment tab.

I'm willing to bet you have a bad/disconnected vacuum line to the wastegate. On the passenger side of the car, a vac line runs from the valve cover down to the boost solenoid. Then a line down to the wastegate. Make sure they are all connected and not damaged.

BimmerNugget · 10-23-2017, 06:03 PM

Quote:

Originally Posted by n55problemdude

328 drivers stay mad

LOL great mentality....You bought a POS 335 and you're too broke too fix it. Looser.

njmian · 03-23-2023, 02:36 PM

Old thread but I’ll post my issue in hopes someone can have some input. So I’m having this constant issue with my bov, I’ve tried 2 new oem and 1 turbosmart bov and turbosmart being the worst imo, always stuck with dirt and even when it was new it wouldn’t open unless i let off the gas above 6psi so I literally threw it in the trash. I’ve checked the diverter valve connection and its clean, i even pressed the pins closer incase it wasn’t getting a good contact but my issue is the after mhd stage 2+ the stock diverter won’t open unless I’m above 4 psi, on light throttles when i let off the gas and I believe when the throttle plate closes i can hear the air howling for like 3 seconds in the pipes stuck trying to escape somewhere. I’ve gone thru 3 turbos snapping off the exhaust wheel every single time, i know turbo wheel break off because of overspin but i have a new wastegate and vacuum solenoid. If this a tuning issue because i am running an OTS map. I’ve just installed a stage 2 hybrid now and when doing full throttle pulls past 70mph acceleration it goes into limp mode saying diverter valve stuck like wtf it works fine when I’m doing light pulls, the car is overboosting but the bov should open when the car does that but its not opening the valve as if the ecu is not telling it to do so.

10-23-2017, 08:56 AM	#1
n55problemdude New Member 3 Rep 23 Posts Drives: 2011 BMW 335xi e92 Coupe Join Date: Oct 2017 Location: 4400 vestal parkway east iTrader: (0)	N55 Low Boost Cont'd Hello Guys, My N55 has had low boost issues for a little over a month now. Changed charge pipe (was cracked), got jb4, intake, down pipes, did oil gasket leak, changed vent hose. Did diagnosis by BMW which they told me to fix my CP, vent hose, and oil gasket. Did smoke test and general diagnosis by Petrol Werks, no problems seen except code: BLOW OFF VALVE JAMMED. Thing is, N55 has a diverter valve so I'm guessing the code is talking about that. They said if I change the DV and nothing helps, then I need to change the turbo. I NEED HELP BECAUSE I DONT WANNA WASTE ANY MORE MONEY ON BS AND HAVE THE CAR STILL LOW BOOSTING. I am able to hear the boost while in the car so it's still spooling. I've noticed little rattling when starting up the car in the morning (cold starts). Also once in a while I hear rattling out the exhausts in the back for about a minute and then it stops. Once I replaced charge pipe, I wasn't getting any reduced power or check engine lights. When I plugged in JB4, I am still low boosting, but now I'm getting reduced engine warnings after like 3-4k rpms but car is still not limp mode! JB4 reads 1-4 psi on average, when I upshift it jumps like 3-4 psi. Any help would be greatly appreciated!! Thanks Last edited by n55problemdude; 10-23-2017 at 01:40 PM.. Reason: I AM DESPERATE FOR ANSWERS D:
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10-23-2017, 10:13 AM	#2
weehe126 Brigadier General 1161 Rep 3,189 Posts Drives: 2017 340i Join Date: Apr 2014 Location: San Antonio iTrader: (2)	FFS stop making new threads and post a damn log. If you are only having this issue with the JB4 you probably have the wrong firmware loaded.
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10-23-2017, 12:12 PM	#4
weehe126 Brigadier General 1161 Rep 3,189 Posts Drives: 2017 340i Join Date: Apr 2014 Location: San Antonio iTrader: (2)	The reason you don't make multiple posts on the same issue is so people can actually follow the progression. It's not my preference, it's everyone's and helps you get help. How do you know you are only getting 1-3 psi? Guessing? In dash gauge? Logging with your computer or phone? How do you know the JB4 is working fine if you are only getting 1-3psi? Was the JB4 installed every time you brought it to the shop? Does it only have 1-3psi with the JB4 removed, how have you checked? This isn't rocket science. It can only be mechanical (boost leak, leaking DV, stuck open wastegate, bad boost solenoid, bad turbo) or electrical (wrong JB4 firmware, or something is unplugged). Go down the list and check things off. You are in college and have a car that drives, stop bitching like it's the end of the world.
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10-23-2017, 01:53 PM	#7
weehe126 Brigadier General 1161 Rep 3,189 Posts Drives: 2017 340i Join Date: Apr 2014 Location: San Antonio iTrader: (2)	You have to answer the rest of my questions for anyone to be able to help. How do you know it is only boosting 1-4psi with JB4 off? Was the JB4 installed when all of the shops looked at it? Unless the DV literally fell out, I doubt the DV is the issue. There is no easy way to verify it's function unless you know what you are looking for. What options and settings are you talking about. You can have the wrong firmware and all the steering wheel/dash stuff will work fine. I have literally uploaded the wrong firmware before and got 1-4psi just like you are saying. Go buy the cable from BMS and post a screen shot of your user adjustments tab as shown above.
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10-23-2017, 05:02 PM	#8
n55problemdude New Member 3 Rep 23 Posts Drives: 2011 BMW 335xi e92 Coupe Join Date: Oct 2017 Location: 4400 vestal parkway east iTrader: (0)	The car was producing equal power with JB4 off and now with it on I can see that it is only producing 1-4 psi on average. JB4 was only installed when petrol werks took a look at it, and they toggled through it to make sure it works. (One of the first things they looked at) I updated the firmware with the usb once I got it, twice, to make sure its compatible with my car settings and etc. People are saying check my waste gate to see if its stuck. I'll try that. Thanks for the help. If you have any additional things you think I should look at or do, please feel free to tell. Thanks again.
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10-23-2017, 05:24 PM	#9
BimmerNugget Crazy Frog 543 Rep 1,211 Posts Drives: L.L.Bean Bootmobile Join Date: Jun 2017 Location: 560 State Street iTrader: (0)	Stop Posting This S**t So Many Goddamn Times! I Swear This Is Like The 4th Thread You've Started On Your Damn Problem. I Will Legit Go To Bing U And Beat You Until You Turn Purple If You Post This Crap One More Time. Stop Being A Cheap Bastard And Get A Proper Bmw Scanner ($140 For Foxwell Nt510) Or Just Take Your Car To An Indy Mechanic.
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03-23-2023, 02:36 PM	#13
njmian New Member 5 Rep 16 Posts Drives: 11' E70 x5 35i, 07' E90 328i Join Date: Aug 2020 Location: Toronto, Canada iTrader: (0)	Old thread but I’ll post my issue in hopes someone can have some input. So I’m having this constant issue with my bov, I’ve tried 2 new oem and 1 turbosmart bov and turbosmart being the worst imo, always stuck with dirt and even when it was new it wouldn’t open unless i let off the gas above 6psi so I literally threw it in the trash. I’ve checked the diverter valve connection and its clean, i even pressed the pins closer incase it wasn’t getting a good contact but my issue is the after mhd stage 2+ the stock diverter won’t open unless I’m above 4 psi, on light throttles when i let off the gas and I believe when the throttle plate closes i can hear the air howling for like 3 seconds in the pipes stuck trying to escape somewhere. I’ve gone thru 3 turbos snapping off the exhaust wheel every single time, i know turbo wheel break off because of overspin but i have a new wastegate and vacuum solenoid. If this a tuning issue because i am running an OTS map. I’ve just installed a stage 2 hybrid now and when doing full throttle pulls past 70mph acceleration it goes into limp mode saying diverter valve stuck like wtf it works fine when I’m doing light pulls, the car is overboosting but the bov should open when the car does that but its not opening the valve as if the ecu is not telling it to do so.
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