Annoying Hesitation/shudder on Acceleration, HELP!!

Nesquik15 · 11-25-2014, 06:52 PM

Hello all, this has been a pita issue for me, I believe this has started to happen after the jb4 was installed, in any map on light acceleration up to 4000 rpm Iam a getting a heavy surge (the car is shuttering/oscillating) its hell of annoying. If you floor it then its pretty smooth no oscillation. I have done a ton of research but couldn't come up with a definite answer. Also I have no fault codes stored. Anyone had same issue? Need some guidance here, thanks to all!

alexg212 · 11-25-2014, 09:01 PM

Carbon build up, injectors, fuel pump, fuel pump, sensor, who knows lol. Need proper diagnosis.

Whiteout335i · 11-26-2014, 11:51 AM

Mines doing the same but only recently now that it's cold if I let it warm up for 20 minutes it won't do it. I know I should get carbon blasted and injectors soon. It is pretty annoying tho

MORTON · 11-26-2014, 12:01 PM

It could be multiple things bro, however, in my direct experience with this in the past I replaced the plugs and coil packs and it solved the problem. It will get worse if that's the case trust me I've been at reduced power on I-95 south.. not cool.. There are many ways to check plugs and coil packs before you go out and buy some (not too cheap..) I suggest you do this before you purchase.. how many miles are on your vehicle and when was the last time these were replaced?

Edit:

Also read the codes at autozone if it says misfire anything more than likely plugs & coil packs.. your check engine light will not necessarily be illuminated either..

Nesquik15 · 11-29-2014, 12:28 PM

SO far I have replaced all plugs, vacum lines, turbos,
Iam starting to think it could be just normal operation of jb4? Its pretty dreadful for a tune to be this jerky

CarAbuser · 11-29-2014, 01:40 PM

Post some logs.

I had the same issue once with my ECU tune. It was caused by poor WGDC control and I remedied it by adjusting my D Factor and D Factor multiplier to smooth out the boost curve.

Nesquik15 · 11-29-2014, 09:43 PM

Quote:

Originally Posted by CarAbuser

Post some logs.

I had the same issue once with my ECU tune. It was caused by poor WGDC control and I remedied it by adjusting my D Factor and D Factor multiplier to smooth out the boost curve.

how is that done? thanks

Andrewah05 · 11-29-2014, 09:53 PM

Loose injector possibly

Ddang06 · 11-29-2014, 10:03 PM

Coils . Mine did the Same thing and new coils solved issues. Replaced sparks prior to that

musc · 11-29-2014, 11:59 PM

Get a log of it and send it to Terry. Lots of people have had boost oscillation at part throttle with the JB4 including myself. Up to 20% throttle adjusting menu 10 and 12 can help. I never had much luck fixing it. It's one of the reasons I wanted to try a flash only tune. No oscillation since going to a flash only.

Nesquik15 · 11-30-2014, 06:59 PM

Quote:

Originally Posted by musc

Get a log of it and send it to Terry. Lots of people have had boost oscillation at part throttle with the JB4 including myself. Up to 20% throttle adjusting menu 10 and 12 can help. I never had much luck fixing it. It's one of the reasons I wanted to try a flash only tune. No oscillation since going to a flash only.

yea I spoke to Terry, I may be going with a flash, which one do you have?

11-25-2014, 06:52 PM	#1
Nesquik15 Private First Class 13 Rep 188 Posts Drives: 335xi Join Date: Sep 2012 Location: United states iTrader: (2)	Annoying Hesitation/shudder on Acceleration, HELP!! Hello all, this has been a pita issue for me, I believe this has started to happen after the jb4 was installed, in any map on light acceleration up to 4000 rpm Iam a getting a heavy surge (the car is shuttering/oscillating) its hell of annoying. If you floor it then its pretty smooth no oscillation. I have done a ton of research but couldn't come up with a definite answer. Also I have no fault codes stored. Anyone had same issue? Need some guidance here, thanks to all! __________________ 2008 335XI//JB4 G5 ISO//AFE STG2 INTAKE//M6 18"//BLACKED OUT TAILS//BLACKED OUT TRIM// F10 550xi/Carbon Black/M-Sport/
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11-25-2014, 09:01 PM	#2
alexg212 Second Lieutenant 53 Rep 278 Posts Drives: 335is Coupe/Mustang Gt Join Date: Oct 2013 Location: DFW iTrader: (0)	Carbon build up, injectors, fuel pump, fuel pump, sensor, who knows lol. Need proper diagnosis.
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11-26-2014, 11:51 AM	#3
Whiteout335i Second Lieutenant 30 Rep 289 Posts Drives: 2010 335i alpine white Join Date: Jul 2013 Location: Nashville, tn iTrader: (1)	Mines doing the same but only recently now that it's cold if I let it warm up for 20 minutes it won't do it. I know I should get carbon blasted and injectors soon. It is pretty annoying tho
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11-26-2014, 12:01 PM	#4
MORTON Major 353 Rep 1,403 Posts Drives: 08' N54 6SPD E90 Join Date: Nov 2014 Location: Palm Coast, FL iTrader: (1)	It could be multiple things bro, however, in my direct experience with this in the past I replaced the plugs and coil packs and it solved the problem. It will get worse if that's the case trust me I've been at reduced power on I-95 south.. not cool.. There are many ways to check plugs and coil packs before you go out and buy some (not too cheap..) I suggest you do this before you purchase.. how many miles are on your vehicle and when was the last time these were replaced? Edit: Also read the codes at autozone if it says misfire anything more than likely plugs & coil packs.. your check engine light will not necessarily be illuminated either..
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11-29-2014, 12:28 PM	#5
Nesquik15 Private First Class 13 Rep 188 Posts Drives: 335xi Join Date: Sep 2012 Location: United states iTrader: (2)	SO far I have replaced all plugs, vacum lines, turbos, Iam starting to think it could be just normal operation of jb4? Its pretty dreadful for a tune to be this jerky __________________ 2008 335XI//JB4 G5 ISO//AFE STG2 INTAKE//M6 18"//BLACKED OUT TAILS//BLACKED OUT TRIM// F10 550xi/Carbon Black/M-Sport/
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11-29-2014, 01:40 PM	#6
CarAbuser Lieutenant Colonel 475 Rep 1,544 Posts Drives: Z4 35i DCT / E92 335i DCT Join Date: Jul 2010 Location: United Kingdom iTrader: (0)	Post some logs. I had the same issue once with my ECU tune. It was caused by poor WGDC control and I remedied it by adjusting my D Factor and D Factor multiplier to smooth out the boost curve.
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11-29-2014, 09:53 PM	#8
Andrewah05 Captain 70 Rep 632 Posts Drives: 335i TiAg Join Date: Sep 2012 Location: Toronto, Canada iTrader: (0)	Loose injector possibly
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11-29-2014, 10:03 PM	#9
Ddang06 Banned 4 Rep 53 Posts Drives: SGM 2007 BMW 335i Join Date: Feb 2013 Location: Sugar Land TX iTrader: (0)	Coils . Mine did the Same thing and new coils solved issues. Replaced sparks prior to that
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11-29-2014, 11:59 PM	#10
musc ****** 184 Rep 1,702 Posts Drives: Audi TTRS, 335is Join Date: Dec 2006 Location: SC iTrader: (9) Garage List 2011 BMW 335is [10.00]	Get a log of it and send it to Terry. Lots of people have had boost oscillation at part throttle with the JB4 including myself. Up to 20% throttle adjusting menu 10 and 12 can help. I never had much luck fixing it. It's one of the reasons I wanted to try a flash only tune. No oscillation since going to a flash only.
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