Turbo lag

CYL · 10-30-2015, 10:25 PM

I tried WOT on 3rd gear last night, however the rpm didn't really climb up quick on wot, with my foot all the way down the gas, the rpm went very slowly and suddenly jumped from 3k to 6k rpm.

I feel like there is a turbo lag but there isn't any fault code...what could be wrong?

I also feel that the car isn't as powerful as before since I last bought it to dealership. It used to very responsive, but lately it just doesn't have that linear power from its twin turbo. But while there isn't any fault code, I don't know where to look at..

Any thoughts please?

CYL · 10-30-2015, 10:42 PM

As I said before, will it be the software update?

http://www.bimmerfile.com/2008/11/18...n54-turbo-lag/

harms · 10-30-2015, 11:59 PM

Boost leak maybe? Under boost codes don't always appear.

kOncept · 10-30-2015, 11:59 PM

are you using JB4?

CYL · 10-31-2015, 12:10 AM

Quote:

Originally Posted by kOncept

are you using JB4?

Haven't used any tune yet

Looking at MHD later and wonder if it is really the software issue, can the aftermarket tune make the instant power back?

CYL · 10-31-2015, 12:11 AM

Quote:

Originally Posted by harms

Boost leak maybe? Under boost codes don't always appear.

May I ask what should I be checking for boost leak?
I have got bmwhat app, but I don't think it has parameter for boost pressure monitoring.

kOncept · 10-31-2015, 12:22 AM

Quote:

Originally Posted by CYL

Haven't used any tune yet

Looking at MHD later and wonder if it is really the software issue, can the aftermarket tune make the instant power back?

not sure if it would fix it, I asked because the latest JB4 firmware update may feel laggy until you adjust Menu 11.
But if you're not using JB4, I have no idea.

Brule · 10-31-2015, 04:27 AM

Check your vacuum lines and maybe your intercooler and chargepipe connections or divertervalves for start.

A new tune wont fix any boost leak

T1M · 10-31-2015, 08:22 PM

Jumped straight from 3k to 6k doesn't sound right. Did the revs climb more rapidly from 3 to 6 or did they "jump" directly from 3 to 6 as you described?

vtl · 10-31-2015, 09:04 PM

Quote:

Originally Posted by cryptik

Jumped straight from 3k to 6k doesn't sound right. Did the revs climb more rapidly from 3 to 6 or did they "jump" directly from 3 to 6 as you described?

Just sounds like an automatic gearbox to me? Put his put down, then the car downshifted.

You said you've done a golf tee mod in your other thread, did you disconnect the vacuum line? If so did you plug it properly? A vacuum leak from the exhaust flap would lead to boost issues.

kOncept · 10-31-2015, 10:07 PM

Here you go, read below.

http://www.e90post.com/forums/showthread.php?t=1013912

Quote:

Originally Posted by Mike@N54Tuning.com

Yes, the JB4 ignores the DME wastegate settings eliminating that lag with 29.2

Mike

10-30-2015, 10:25 PM	#1
CYL Major 129 Rep 1,382 Posts Drives: E92 Join Date: Aug 2013 Location: Australia iTrader: (0)	Turbo lag I tried WOT on 3rd gear last night, however the rpm didn't really climb up quick on wot, with my foot all the way down the gas, the rpm went very slowly and suddenly jumped from 3k to 6k rpm. I feel like there is a turbo lag but there isn't any fault code...what could be wrong? I also feel that the car isn't as powerful as before since I last bought it to dealership. It used to very responsive, but lately it just doesn't have that linear power from its twin turbo. But while there isn't any fault code, I don't know where to look at.. Any thoughts please?
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10-30-2015, 10:42 PM	#2
CYL Major 129 Rep 1,382 Posts Drives: E92 Join Date: Aug 2013 Location: Australia iTrader: (0)	As I said before, will it be the software update? http://www.bimmerfile.com/2008/11/18...n54-turbo-lag/
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10-30-2015, 11:59 PM	#3
harms Captain 75 Rep 605 Posts Drives: 335i Join Date: Jul 2014 Location: Australia iTrader: (0)	Boost leak maybe? Under boost codes don't always appear.
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10-30-2015, 11:59 PM	#4
kOncept First Lieutenant 36 Rep 303 Posts Drives: E92 335i Join Date: Feb 2011 Location: AUS iTrader: (0)	are you using JB4?
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10-31-2015, 04:27 AM	#8
Brule Brigadier General 827 Rep 3,189 Posts Drives: 2007 335i e92 6spd man Join Date: Jul 2013 Location: Darwin iTrader: (0)	Check your vacuum lines and maybe your intercooler and chargepipe connections or divertervalves for start. A new tune wont fix any boost leak
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10-31-2015, 08:22 PM	#9
T1M Captain 196 Rep 657 Posts Drives: AW MY12 1M Join Date: Jun 2015 Location: Melbourne, Australia iTrader: (0)	Jumped straight from 3k to 6k doesn't sound right. Did the revs climb more rapidly from 3 to 6 or did they "jump" directly from 3 to 6 as you described?
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