Lag, but no rattle . . .

jozza66 · 12-21-2011, 05:01 AM

Hi,

Took my 56 plate 335i in yesterday to be looked at by Sytner in Ascot...been suffering with lag and turbo noise, that manifests itself as a feeling like I'm down on power. Apparently the cars showing no error codes, but they did change the gearbox oil due to "slippage" . . .

So, well aware of the documented issues with N54 wastegates etc, but currently I've got no rattle but a good 3/4 -1 s of Lag when nailing the throttle. Additionally there's more whine than normal during the lag period... any ideas? Car's done 18K, fully up to date on servicing and no engine mods...

John.

idnan · 12-21-2011, 10:13 AM

Did the dealers do any software updates to the car? Apparently different software versions adjust the wastegate position on the turbos to reduce rattle but can induce lag.

The only other thing I can think of is resetting a few of the adaptations (I think there is one for the throttle valve) and see how that goes. It's pretty easy to do if you've got the appropriate cable.

jozza66 · 12-21-2011, 10:31 AM

No updates yesterday to my knowledge, and the problem was there prior to the visit, but not from the point I bought the car... may invest in the cable, or start the merry-go-round of finding a tech at the dealers who'll drive it and recreate the issue....

neil@JuicedUpTuning · 12-21-2011, 02:28 PM

JB4 with USB Cable...provides a window into whats happening with the car...and gives you a boat load of power to boot...

- Can reset adaptions
- Reads and Deletes all codes
- Provides logs of whats happenning to the car. Easy to do
- Has Lagfix and Bogfix (Reduces/removes lag)
- Maps to give you 350 wheel horse power for a stock car

geterdone · 02-01-2012, 09:55 PM

After searching the forums numerous times, I thought I would see if you knew by chance what bogfix and lagfix actually does mechanically and performance wise.

doughboy · 02-02-2012, 02:47 AM

On a 56 car, its out of warranty so why not take it to a top-notch 335i specialist like Birds in Uxbridge, they'll have a sympathetic ear to your problem and WILL diagnose it for you.

Don't bother with a dealer tech, they just don't give a shit unfortunately, just a job to them.

PS - Birds can do pukka software updates etc too if needed.

nicktyler · 02-02-2012, 03:45 AM

Is it not normal to have a bit of lag? I have an evolve stage 1 on mine and there is a tiny bit of lag but not any more than when it was stock. It might seem to be longer as when the power does come on it is so much stronger?

I haven't tried to time it but I thought it was normal especially from the lower rev range?

12-21-2011, 05:01 AM	#1
jozza66 Private First Class 19 Rep 135 Posts Drives: F31 335dx Join Date: Aug 2011 Location: Surrey, UK iTrader: (2)	Lag, but no rattle . . . Hi, Took my 56 plate 335i in yesterday to be looked at by Sytner in Ascot...been suffering with lag and turbo noise, that manifests itself as a feeling like I'm down on power. Apparently the cars showing no error codes, but they did change the gearbox oil due to "slippage" . . . So, well aware of the documented issues with N54 wastegates etc, but currently I've got no rattle but a good 3/4 -1 s of Lag when nailing the throttle. Additionally there's more whine than normal during the lag period... any ideas? Car's done 18K, fully up to date on servicing and no engine mods... John. __________________ ------------------------------------------------------ Past Previous: E92 335i, CIC retrofit, JB+, Perf Exhaust Last Car: MB ML350CDI, X800D-ML Retrofit, AMG Steering wheel, Brabus tuning box Current car: F31 335d - NBT EVO ID6 retrofit, 3AG retrofit, Coded EBT, Deleted RFTs!!
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12-21-2011, 10:13 AM	#2
idnan Lieutenant Colonel 76 Rep 1,518 Posts Drives: Alpine White 335i Join Date: Nov 2010 Location: Birmingham iTrader: (9)	Did the dealers do any software updates to the car? Apparently different software versions adjust the wastegate position on the turbos to reduce rattle but can induce lag. The only other thing I can think of is resetting a few of the adaptations (I think there is one for the throttle valve) and see how that goes. It's pretty easy to do if you've got the appropriate cable.
	Appreciate 0 Quote

12-21-2011, 10:31 AM	#3
jozza66 Private First Class 19 Rep 135 Posts Drives: F31 335dx Join Date: Aug 2011 Location: Surrey, UK iTrader: (2)	No updates yesterday to my knowledge, and the problem was there prior to the visit, but not from the point I bought the car... may invest in the cable, or start the merry-go-round of finding a tech at the dealers who'll drive it and recreate the issue.... __________________ ------------------------------------------------------ Past Previous: E92 335i, CIC retrofit, JB+, Perf Exhaust Last Car: MB ML350CDI, X800D-ML Retrofit, AMG Steering wheel, Brabus tuning box Current car: F31 335d - NBT EVO ID6 retrofit, 3AG retrofit, Coded EBT, Deleted RFTs!!
	Appreciate 0 Quote

12-21-2011, 02:28 PM	#4
neil@JuicedUpTuning 14 Rep 454 Posts Drives: BMW 135i Join Date: Aug 2010 Location: UK iTrader: (1)	JB4 with USB Cable...provides a window into whats happening with the car...and gives you a boat load of power to boot... - Can reset adaptions - Reads and Deletes all codes - Provides logs of whats happenning to the car. Easy to do - Has Lagfix and Bogfix (Reduces/removes lag) - Maps to give you 350 wheel horse power for a stock car
	Appreciate 0 Quote

02-01-2012, 09:55 PM	#5
geterdone Private First Class 5 Rep 144 Posts Drives: 2007 335i Join Date: Mar 2011 Location: Yukon, Oklahoma iTrader: (1)	After searching the forums numerous times, I thought I would see if you knew by chance what bogfix and lagfix actually does mechanically and performance wise.
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02-02-2012, 02:47 AM	#6
doughboy Major General 1546 Rep 8,972 Posts Drives: 2018 M2 Comp 6MT Join Date: Jan 2009 Location: UK iTrader: (2)	On a 56 car, its out of warranty so why not take it to a top-notch 335i specialist like Birds in Uxbridge, they'll have a sympathetic ear to your problem and WILL diagnose it for you. Don't bother with a dealer tech, they just don't give a shit unfortunately, just a job to them. PS - Birds can do pukka software updates etc too if needed.
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02-02-2012, 03:45 AM	#7
nicktyler Major 32 Rep 1,271 Posts Drives: 335i (sadly gone) Join Date: Jan 2012 Location: Essex iTrader: (3) Garage List 2007 BMW E92 335i [0.00]	Is it not normal to have a bit of lag? I have an evolve stage 1 on mine and there is a tiny bit of lag but not any more than when it was stock. It might seem to be longer as when the power does come on it is so much stronger? I haven't tried to time it but I thought it was normal especially from the lower rev range?
	Appreciate 0 Quote