E90Post
 


ECS BMW
 
BMW 3-Series (E90 E92) Forum > E90 / E92 / E93 3-series Powertrain and Drivetrain Discussions > N54 Turbo Engine / Drivetrain / Exhaust Modifications - 335i > What causes throttle closing when WOT?



Reply
 
Thread Tools Search this Thread
      05-09-2013, 10:39 PM   #1
BADS335
First Lieutenant
8
Rep
394
Posts

 
Drives: Montego 335i E90
Join Date: Sep 2010
Location: Chicago

iTrader: (2)

What causes throttle closing when WOT?

Ok, so I have a ProCede and log as much as I can. I noticed a drop in power quite often in the 4k-5k range. When looking at logs throttle shows 100% but CAN DME throttle dips down into the 70s and 80s and sometimes even way lower. Traction control and stability control are off. No KR. What else causes the TB to close?
__________________
2008-BMW-335i-E90-6MT-Sport-Montego Blue
Appreciate 0
      05-09-2013, 11:51 PM   #2
VNeBLOB42
Lieutenant Colonel
VNeBLOB42's Avatar
United_States
20
Rep
1,679
Posts

 
Drives: 14' GMC Terrain SLT-2
Join Date: May 2011
Location: Folsom, Ca

iTrader: (0)

Garage List
007 335i E92  [3.83]
Send a message via Skype™ to VNeBLOB42
Over boost?
__________________

SOLD:: PTF Pro eTune by Dzenno / COBB S1+ E50
Alpina B3 Flash / ETS FMIC / ER CP / CPE DCI
Appreciate 0
      05-13-2013, 02:06 PM   #3
BADS335
First Lieutenant
8
Rep
394
Posts

 
Drives: Montego 335i E90
Join Date: Sep 2010
Location: Chicago

iTrader: (2)

Not looking like overboost.

I need help understanding everything that would close the TB. No KR detected. No other issues detected. Its frustrating cause you feel the drop in power when it does this pretty dramatically.
Appreciate 0
      05-13-2013, 02:07 PM   #4
Jeff@TopGearSolutions
BimmerPost Supporting Vendor
Jeff@TopGearSolutions's Avatar
United_States
243
Rep
18,310
Posts


 
Drives: C6 Z06, GSXR-750, 09 335i
Join Date: Dec 2008
Location: TopGearSolutions.com

iTrader: (32)

Send a message via AIM to Jeff@TopGearSolutions
Post a log?
Appreciate 0
      05-13-2013, 02:26 PM   #5
wingman88
New Member
wingman88's Avatar
0
Rep
8
Posts

 
Drives: E91 335i N54
Join Date: Oct 2012
Location: Aschaffenburg

iTrader: (0)

same problem here! perhaps the diverter valves are weak....?
Appreciate 0
      05-13-2013, 03:29 PM   #6
BADS335
First Lieutenant
8
Rep
394
Posts

 
Drives: Montego 335i E90
Join Date: Sep 2010
Location: Chicago

iTrader: (2)

I don't know what would cause the TB to close to know what to log. I have a log showing the TB closing at WOT. What should I show in the charts? Obviously throttle and DBW throttle, RPM, DBW boost actual. What else would be relevant? I have all the typical criticals. But no WG data.
Appreciate 0
      05-13-2013, 03:57 PM   #7
BADS335
First Lieutenant
8
Rep
394
Posts

 
Drives: Montego 335i E90
Join Date: Sep 2010
Location: Chicago

iTrader: (2)

See attached. This is a 3rd gear pull. There is a dip later in the pull that goes down to 73%. This isn't nearly as bad as some situations. But you can see it dropped below 80% then slowly came back then dipped again.
Attached Images
 
__________________
2008-BMW-335i-E90-6MT-Sport-Montego Blue
Appreciate 0
      05-13-2013, 09:58 PM   #8
MrRager
First Lieutenant
MrRager's Avatar
United_States
5
Rep
383
Posts

 
Drives: 335i
Join Date: Jul 2011
Location: 73134

iTrader: (0)

shouldnt the throttle body always be wide open? or is that only on the N52 and N55?
__________________
2008 335i 6MT
Appreciate 0
      05-14-2013, 07:57 AM   #9
BADS335
First Lieutenant
8
Rep
394
Posts

 
Drives: Montego 335i E90
Join Date: Sep 2010
Location: Chicago

iTrader: (2)

Quote:
Originally Posted by MrRager View Post
shouldnt the throttle body always be wide open? or is that only on the N52 and N55?
This is exactly what I am trying to figure out. And what would cause it to close.
Appreciate 0
      05-14-2013, 08:27 AM   #10
BADS335
First Lieutenant
8
Rep
394
Posts

 
Drives: Montego 335i E90
Join Date: Sep 2010
Location: Chicago

iTrader: (2)

Logged yesterday and this time the throttle opening time was really slow after a shift into 3rd.
__________________
2008-BMW-335i-E90-6MT-Sport-Montego Blue
Appreciate 0
      05-14-2013, 09:46 PM   #11
JamesM3M5
Some dude
United_States
24
Rep
1,760
Posts

 
Drives: E28 M5, E92 335i
Join Date: Sep 2011
Location: Northern VA

iTrader: (0)

Quote:
Originally Posted by MrRager View Post
shouldnt the throttle body always be wide open? or is that only on the N52 and N55?
No, the N54 has a traditional throttle, not like Valvetronic or stratified charge running.

Throttle closures come from boost exceeding target, especially after quick shifts without a full throttle lift.. Any boost leaks or wastegate troubles?
__________________
RRT Racing
E92 335i/6MT Dinan Stage 3: intercooler, oil cooler, intake, flash, exhaust, LW dual-mass flywheel.
Vishnu PWM methanol custom trunk mount, Diffsonline 3-clutch Salisbury custom diff, Ohlins Road and Track coilovers, Vorshlag camber plates, much more...
E28 M5 w/ buncha stuff, R171 SLK350
Appreciate 0
      05-15-2013, 03:30 AM   #12
cstavaru
Brigadier General
cstavaru's Avatar
94
Rep
3,237
Posts

 
Drives: 2009 335i M Sport Sedan 6MT
Join Date: Aug 2008
Location: Bucharest, Romania

iTrader: (0)

Quote:
Originally Posted by BADS335 View Post
This is exactly what I am trying to figure out. And what would cause it to close.
I can't see your boost target in the log picture. Put boost and boost target on the same graph (if possible). Throttle closure at WOT is almost always caused by actual boost exceeding the boost target.

Moreover, the throttle maximum opening is about 81.08, so it does not "dip" into the 80s or 70s, 70 is a minor throttle closure. It may be that the graph is misleading you.
Appreciate 0
      05-15-2013, 08:13 AM   #13
BADS335
First Lieutenant
8
Rep
394
Posts

 
Drives: Montego 335i E90
Join Date: Sep 2010
Location: Chicago

iTrader: (2)

Quote:
Originally Posted by cstavaru View Post
I can't see your boost target in the log picture. Put boost and boost target on the same graph (if possible). Throttle closure at WOT is almost always caused by actual boost exceeding the boost target.

Moreover, the throttle maximum opening is about 81.08, so it does not "dip" into the 80s or 70s, 70 is a minor throttle closure. It may be that the graph is misleading you.
Yeah I logged the wrong boost target. I logged DME target which only shows factory setting. I will try logging this and see if the events line up.

Actually on the throttle it will read up tp 99% so when it goes below it is definately closing.

Thanks
__________________
2008-BMW-335i-E90-6MT-Sport-Montego Blue
Appreciate 0
      05-15-2013, 08:53 AM   #14
cstavaru
Brigadier General
cstavaru's Avatar
94
Rep
3,237
Posts

 
Drives: 2009 335i M Sport Sedan 6MT
Join Date: Aug 2008
Location: Bucharest, Romania

iTrader: (0)

Quote:
Originally Posted by BADS335 View Post
Actually on the throttle it will read up tp 99% so when it goes below it is definately closing.
The 99% one is the pedal reading, not the throttle. That is, if Procede is not different in logging than any other tool like BT, Cobb or JB4.
Appreciate 0
      05-15-2013, 01:38 PM   #15
BADS335
First Lieutenant
8
Rep
394
Posts

 
Drives: Montego 335i E90
Join Date: Sep 2010
Location: Chicago

iTrader: (2)

I do not know what the node is that is being measured, but they call it "throttle" and it appears to follow the pedal. And DBW throttle appears to be the throttle blade possition.
Appreciate 0
Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 05:23 PM.




e90post
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST