surging/flucuations while crusing in vaccuum

TT3 iN NyC · 05-20-2012, 04:36 PM

Hi all,

I noticed that when I'm cruising, not in boost, the car feels jerky/surging/hesitating. You can actually feel the jerking/hesitation, sort of like it wants to pull.

This only happens when I keep the throttle constant, not giving gas, to maintain a constant speed limit. It doesn't happen while the car is idling or when in boost.

When I give gas, it'll go away but does come back sooner or later.

Anyone have any ideas what it could be? Video below

Thanks!

skinrock · 05-20-2012, 04:51 PM

Video is private.

TT3 iN NyC · 05-20-2012, 05:05 PM

Quote:

Originally Posted by skinrock

Video is private.

Thanks! Changed to public

OpenFlash · 05-20-2012, 05:09 PM

What bypass/bov are you running?

TT3 iN NyC · 05-20-2012, 05:11 PM

Quote:

Originally Posted by shiv@vishnu

What bypass/bov are you running?

Stett chargepipe with forged DV's

OpenFlash · 05-20-2012, 05:14 PM

Quote:

Originally Posted by TT3 iN NyC

Stett chargepipe with forged DV's

I've run into this problem when the spring setting in the bypass valve is too soft and starts to crack open/close/open when cruising at a high enough RPM to make positive boost pressure when cruising. I solved it by running a stiffer spring (yellow). Do you know what springs you are running?

Jeff@TopGearSolutions · 05-20-2012, 05:20 PM

Have you been using map 3?

TT3 iN NyC · 05-20-2012, 05:26 PM

[QUOTE=I've run into this problem when the spring setting in the bypass valve is too soft and starts to crack open/close/open when cruising at a high enough RPM to make positive boost pressure when cruising. I solved it by running a stiffer spring (yellow). Do you know what springs you are running?[/QUOTE]

Yup, I'm running the yellow springs. I'm pretty positive. I just checked the box, there is a set of blue and a set of green springs in there.

TT3 iN NyC · 05-20-2012, 05:26 PM

Quote:

Originally Posted by Jeff@topgearsolutions

Have you been using map 3?

Not at all. I only use map 1

TT3 iN NyC · 05-20-2012, 07:43 PM

Anyone? =)

Evelyn · 05-20-2012, 07:49 PM

I have the same set up and the same issue. But I believe I am running the green spring, I'm gonna try a different one.

TT3 iN NyC · 05-20-2012, 07:55 PM

Quote:

Originally Posted by Evelyn

I have the same set up and the same issue. But I believe I am running the green spring, I'm gonna try a different one.

Yellow are the stiffest? Or is there one that's stiffer?

badass335 · 05-20-2012, 10:06 PM

Which map/firmware are you running? The latest 4-23?

TT3 iN NyC · 05-20-2012, 10:24 PM

Quote:

Originally Posted by badass335

Which map/firmware are you running? The latest 4-23?

Yup, latest 4/23 map/firmware. However, I made this video on map 0 (stock).

BOosted 335i · 05-20-2012, 10:36 PM

i am noticing this too but what i have is if cruising at around 60mph at 2000 rpms with slight gas pedal pressure for awhile i see boost guage surge up like 1 psi or so quickly then back but not all the time.i have a tial bov with std spring no color just metal.maybe it could be that?Maybe get a harder one?

badass335 · 05-20-2012, 11:21 PM

Just curious if this happens on the 3-17 maps. I would suggest you try those and see if it happens?

TT3 iN NyC · 05-21-2012, 08:07 AM

Quote:

Originally Posted by badass335

Just curious if this happens on the 3-17 maps. I would suggest you try those and see if it happens?

Even if it occurs on map 0?

Fedie · 05-21-2012, 08:20 AM

Which color springs do you have in the valves?

TT3 iN NyC · 05-21-2012, 09:27 AM

Quote:

Originally Posted by Fedie

Which color springs do you have in the valves?

I have the yellow springs. These are the stiffest correct?

zerep1 · 05-21-2012, 10:11 AM

Quote:

Originally Posted by Jeff@topgearsolutions

Have you been using map 3?

what are the issues with this i never gotten a straight answer other then something about adaptations

TT3 iN NyC · 05-21-2012, 10:37 AM

Will resetting adaptations resolve this issue?

jpsimon · 05-21-2012, 10:50 AM

It's easy enough to do, give it a try

05-20-2012, 04:36 PM	#1
TT3 iN NyC Colonel 247 Rep 2,567 Posts Drives: F80 M3CS Join Date: Aug 2007 Location: nYc iTrader: (9)	surging/flucuations while crusing in vaccuum Hi all, I noticed that when I'm cruising, not in boost, the car feels jerky/surging/hesitating. You can actually feel the jerking/hesitation, sort of like it wants to pull. This only happens when I keep the throttle constant, not giving gas, to maintain a constant speed limit. It doesn't happen while the car is idling or when in boost. When I give gas, it'll go away but does come back sooner or later. Anyone have any ideas what it could be? Video below Thanks! __________________ 07 e92 335i - Retired 18 F80 M3CS - Retired 21 G20 330i M-Sport - Current
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05-20-2012, 04:51 PM	#2
skinrock Agent Smith 270 Rep 3,344 Posts Drives: 2016 i8 Join Date: Jan 2011 Location: The Matrix iTrader: (9) Garage List 2016 BMW i8 [10.00]	Video is private. __________________ The i8 needs a V8 amirite?
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05-20-2012, 05:09 PM	#4
OpenFlash 1737 Rep 17,960 Posts Drives: A Lot Join Date: Sep 2006 Location: SF Bay, CA iTrader: (0) Garage List 2018 Ducati Panigal ... [0.00] 2016 Mazda CX5 [0.00] 2017 Aprilia Tuono ... [0.00] 2019 BMW M2 Competi ... [0.00] 2015 BMW M5 Competi ... [10.00] 2016 Ducati XDiavel S [0.00] 2016 AMG GT S [0.00] 2011 Ferrari 458 It ... [0.00] 2017 Charger Hellcat [0.00] 2015 KTM Super Duke ... [0.00] 2016 KTM RC390 [0.00]	What bypass/bov are you running?
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05-20-2012, 05:20 PM	#7
Jeff@TopGearSolutions 3441 Rep 79,211 Posts Drives: C6 Z06, 09 335i, 10 335xi Join Date: Dec 2008 Location: www.TopGearSolutions.com iTrader: (37)	Have you been using map 3?
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05-20-2012, 05:26 PM	#8
TT3 iN NyC Colonel 247 Rep 2,567 Posts Drives: F80 M3CS Join Date: Aug 2007 Location: nYc iTrader: (9)	[QUOTE=I've run into this problem when the spring setting in the bypass valve is too soft and starts to crack open/close/open when cruising at a high enough RPM to make positive boost pressure when cruising. I solved it by running a stiffer spring (yellow). Do you know what springs you are running?[/QUOTE] Yup, I'm running the yellow springs. I'm pretty positive. I just checked the box, there is a set of blue and a set of green springs in there. __________________ 07 e92 335i - Retired 18 F80 M3CS - Retired 21 G20 330i M-Sport - Current
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05-20-2012, 07:43 PM	#10
TT3 iN NyC Colonel 247 Rep 2,567 Posts Drives: F80 M3CS Join Date: Aug 2007 Location: nYc iTrader: (9)	Anyone? =) __________________ 07 e92 335i - Retired 18 F80 M3CS - Retired 21 G20 330i M-Sport - Current
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05-20-2012, 07:49 PM	#11
Evelyn Private 1 Rep 54 Posts Drives: 335i M Join Date: Aug 2011 Location: Washington iTrader: (0) Garage List 2008 335 m [5.00]	I have the same set up and the same issue. But I believe I am running the green spring, I'm gonna try a different one.
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05-20-2012, 10:06 PM	#13
badass335 Lieutenant Colonel 109 Rep 1,948 Posts Drives: 2017 540i Xdrive Join Date: Jul 2007 Location: Surrey, BC iTrader: (10)	Which map/firmware are you running? The latest 4-23?
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05-20-2012, 10:36 PM	#15
BOosted 335i //Thumper 3 Rep 82 Posts Drives: BMW Join Date: Jul 2010 Location: Tri-State East Coast iTrader: (0)	i am noticing this too but what i have is if cruising at around 60mph at 2000 rpms with slight gas pedal pressure for awhile i see boost guage surge up like 1 psi or so quickly then back but not all the time.i have a tial bov with std spring no color just metal.maybe it could be that?Maybe get a harder one?
	Appreciate 0 Quote

05-20-2012, 11:21 PM	#16
badass335 Lieutenant Colonel 109 Rep 1,948 Posts Drives: 2017 540i Xdrive Join Date: Jul 2007 Location: Surrey, BC iTrader: (10)	Just curious if this happens on the 3-17 maps. I would suggest you try those and see if it happens?
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05-21-2012, 08:20 AM	#18
Fedie Second Lieutenant 34 Rep 224 Posts Drives: '18 M2 Join Date: Feb 2011 Location: Hamilton iTrader: (0) Garage List 2007 BMW 335i E92 [0.00]	Which color springs do you have in the valves? __________________ M2 LCI bone stock Recently gone, i3 on H&R Springs Long gone, Le Mans Blue X1 xdrive35 M-Sport - Alpina TCU flash - HR springs - Catless dp - JB4 ST2 - CAI -- Alpine White 2007 335i E92 - Procede v3 Stg 2/3 custom - VRSP 3" DP - Stett charge + Forge DV - Stett CAI - CXracing IC
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05-21-2012, 10:37 AM	#21
TT3 iN NyC Colonel 247 Rep 2,567 Posts Drives: F80 M3CS Join Date: Aug 2007 Location: nYc iTrader: (9)	Will resetting adaptations resolve this issue? __________________ 07 e92 335i - Retired 18 F80 M3CS - Retired 21 G20 330i M-Sport - Current
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05-21-2012, 10:50 AM	#22
jpsimon Team Zissou 3065 Rep 10,197 Posts Drives: 2022 AWD M3 Comp - SMB Join Date: Dec 2006 Location: CT iTrader: (7)	It's easy enough to do, give it a try
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