E90Post
 


 
BMW 3-Series (E90 E92) Forum > E90 / E92 / E93 3-series Powertrain and Drivetrain Discussions > N54 Turbo Engine / Drivetrain / Exhaust Modifications - 335i > SOLVED: N54 Oscillating throttle position/surge at steady speed



Reply
 
Thread Tools Search this Thread
      12-18-2020, 02:39 PM   #1
Wadger
Enlisted Member
20
Rep
48
Posts

Drives: BMW 335i
Join Date: Mar 2019
Location: Milton Keynes

iTrader: (0)

SOLVED: N54 Oscillating throttle position/surge at steady speed

Good evening all,

Been noticing a slight surging when holding steady speeds or when using cruise control.
Especially on one flat road I use for work.
It's like the engine speeds up, then slows because it sped up, spiraling to the point where I get a constant up and down.
Were talking 30rpm here however I'm concerned.

I'm running mhd 2+ full bolt on.
Index 12 injectors not sure if age
Coils, plugs, o2's, turbo cores and wastegates, dp's, intercooler, gearbox oil, boost solenoids all done well under 3k ago.
Oil changed 250 miles ago.

This has only really presented itself since the tune and I've only really started noticing now I drive it every day to work.
And once it get going it seems to consistant to Be a vacuum leak? See attached image of log.

Anyone have any thoughts? Was lucky when I run this log it done it at its worst.

Car idles fine, wot is fine, drives great. Hpfp pressures seem with range and constant under wot. Same with lpfp.

Hopefully someone has experienced similar?
Name:  Screenshot_20201218-203700.jpg
Views: 2972
Size:  202.4 KB
Thanks!

Last edited by Wadger; 08-08-2021 at 12:05 PM..
Appreciate 0
      12-18-2020, 02:48 PM   #2
torrque
Banned
297
Rep
650
Posts

Drives: Ferrari F430, E92 M3, 335xi
Join Date: Apr 2014
Location: Newton, MA

iTrader: (0)

Garage List
2005 Ferrari F430  [9.08]
2009 BMW M3  [10.00]
2008 BMW 335xi  [0.00]
Yep, had that on my MHD v9.0 maps. Went back to 8, gone. Also, if you delete adaptations, it will go away for a while...
Appreciate 0
      12-18-2020, 02:51 PM   #3
Wadger
Enlisted Member
20
Rep
48
Posts

Drives: BMW 335i
Join Date: Mar 2019
Location: Milton Keynes

iTrader: (0)

Thanks for the rapid response.
It does seem adaption related maybe as it definitely appears to be getting more noticible the more I use cruise control.
Im currently running the v8 map, I'll try the reset on the throttle only?
Thanks again.
Appreciate 0
      12-18-2020, 02:53 PM   #4
torrque
Banned
297
Rep
650
Posts

Drives: Ferrari F430, E92 M3, 335xi
Join Date: Apr 2014
Location: Newton, MA

iTrader: (0)

Garage List
2005 Ferrari F430  [9.08]
2009 BMW M3  [10.00]
2008 BMW 335xi  [0.00]
Are you in Bukinghamshire, UK? I have a good friend working for Santander in Milton Keynes... I plan on visiting him when this bullshit is over.
Appreciate 0
      12-18-2020, 02:54 PM   #5
torrque
Banned
297
Rep
650
Posts

Drives: Ferrari F430, E92 M3, 335xi
Join Date: Apr 2014
Location: Newton, MA

iTrader: (0)

Garage List
2005 Ferrari F430  [9.08]
2009 BMW M3  [10.00]
2008 BMW 335xi  [0.00]
Quote:
Originally Posted by Wadger View Post
Thanks for the rapid response.
It does seem adaption related maybe as it definitely appears to be getting more noticible the more I use cruise control.
Im currently running the v8 map, I'll try the reset on the throttle only?
Thanks again.
Reset all adaptations, won't hurt ... Make sure to wait for a few minutes before re-starting, or you'll get the bouncing revs issue.
Appreciate 0
      12-18-2020, 02:57 PM   #6
Wadger
Enlisted Member
20
Rep
48
Posts

Drives: BMW 335i
Join Date: Mar 2019
Location: Milton Keynes

iTrader: (0)

Ye I'm in Milton Keynes.
I've had this car a year and I'm always paranoid about it ��.
Thanks for the advice.
Appreciate 0
      12-18-2020, 02:58 PM   #7
Wadger
Enlisted Member
20
Rep
48
Posts

Drives: BMW 335i
Join Date: Mar 2019
Location: Milton Keynes

iTrader: (0)

I'll be going down the same route Monday on the suspect road. So I'll log again and post up the results of the reset
Appreciate 0
      12-18-2020, 04:41 PM   #8
Saif2018
Brigadier General
972
Rep
3,219
Posts

Drives: E90 335i
Join Date: Jan 2019
Location: UK

iTrader: (0)

Quote:
Originally Posted by torrque View Post
Yep, had that on my MHD v9.0 maps. Went back to 8, gone. Also, if you delete adaptations, it will go away for a while...
I wouldn't recommend v8 maps, several users issues with it, including throttle closures if I recall correctly.

V9 has zero throttle closures, I've ran both v7 and v9, both run fine.

Last edited by Saif2018; 12-19-2020 at 10:49 AM..
Appreciate 0
      12-18-2020, 04:42 PM   #9
Saif2018
Brigadier General
972
Rep
3,219
Posts

Drives: E90 335i
Join Date: Jan 2019
Location: UK

iTrader: (0)

Quote:
Originally Posted by Wadger View Post
Thanks for the rapid response.
It does seem adaption related maybe as it definitely appears to be getting more noticible the more I use cruise control.
Im currently running the v8 map, I'll try the reset on the throttle only?
Thanks again.
Recommended you flash v9 map and then relog after driving the car for a while.
Appreciate 0
      12-19-2020, 07:19 AM   #10
Wadger
Enlisted Member
20
Rep
48
Posts

Drives: BMW 335i
Join Date: Mar 2019
Location: Milton Keynes

iTrader: (0)

Thanks for the response. I'll flash today and log through the week going to work.
Thanks again!
Appreciate 0
      12-19-2020, 10:52 AM   #11
Saif2018
Brigadier General
972
Rep
3,219
Posts

Drives: E90 335i
Join Date: Jan 2019
Location: UK

iTrader: (0)

Quote:
Originally Posted by Wadger View Post
Thanks for the response. I'll flash today and log through the week going to work.
Thanks again!
No worries, post the link to the V9 log afterwards,
Appreciate 0
      12-21-2020, 12:54 AM   #12
riczon.335i
Second Lieutenant
riczon.335i's Avatar
48
Rep
233
Posts

Drives: 2007 BMW 335i Coupe
Join Date: Aug 2014
Location: Washington State

iTrader: (1)

I was getting these issues on V9 I thought I was just going crazy but went back to V7.1 all is good now. Also the v9 maps kept giving me Mixture 1 & 2 Codes.

Quote:
Originally Posted by Wadger View Post
Good evening all,

Been noticing a slight surging when holding steady speeds or when using cruise control.
Especially on one flat road I use for work.
It's like the engine speeds up, then slows because it sped up, spiraling to the point where I get a constant up and down.
Were talking 30rpm here however I'm concerned.

I'm running mhd 2+ full bolt on.
Index 12 injectors not sure if age
Coils, plugs, o2's, turbo cores and wastegates, dp's, intercooler, gearbox oil, boost solenoids all done well under 3k ago.
Oil changed 250 miles ago.

This has only really presented itself since the tune and I've only really started noticing now I drive it every day to work.
And once it get going it seems to consistant to Be a vacuum leak? See attached image of log.

Anyone have any thoughts? Was lucky when I run this log it done it at its worst.

Car idles fine, wot is fine, drives great. Hpfp pressures seem with range and constant under wot. Same with lpfp.

Hopefully someone has experienced similar?
Attachment 2485909
Thanks!
Appreciate 0
      12-21-2020, 02:50 PM   #13
iqraceworks
Brigadier General
iqraceworks's Avatar
1981
Rep
3,715
Posts

Drives: 2007 335i
Join Date: Aug 2019
Location: Missouri

iTrader: (0)

I had the exact same issue after running the V7 stage 2+ tune for about a month. Heading down the road at 40mph and I could start to feel a very slight surging feeling. Got on the highway, set the cruise, and then I started to feel it again....a very slight pulsing/surging feeling. I should have tried to do a log first, but at the next exit I got off the highway and shut the car off.

I got out my cable and got MHD fired up on my phone so I could run a log when I got back on the highway. I fired the car up....got on the highway, never did the surging again.

For the hell of it, on the way home I did a WOT pull and noticed that my LPFP pressure was dipping down into the 40's.....it was getting week. I parked the car, and installed a stage 2 LPFP a few days after......never have had an issue since. I did shortly switch over to the V5 E40 tune after the new pump.

Unfortunately, since I didn't log anything....I have no idea was actually caused the pulsing feeling like that......but it sounds like exactly what was happening in the original post. Could have been the tune, could have been the LPFP, could have been something else...
Appreciate 0
      12-22-2020, 12:18 PM   #14
Wadger
Enlisted Member
20
Rep
48
Posts

Drives: BMW 335i
Join Date: Mar 2019
Location: Milton Keynes

iTrader: (0)

Tha ks for the input guys.

A quick update:
So I flashed v9 map and done a throttle reset.
The issue is still present, however it doesn't seem as bad. I noticed a similar surging when in 1st gear when I was rolling out the car park, but not sure if that's just me moving the pedal a little or being paranoid.
Maybe it's learning still and will fade out, in my haste to get home for dinner I forgot to do a log.
However I've put a reminder on my phone for tomorrow
On a side note, the boost kicks in significantly harder on in the lower rpm's than the v8. Wernt far of parking in the boot of the car I was overtaking

Thanks again to all that have commented
Appreciate 0
      12-22-2020, 12:44 PM   #15
iqraceworks
Brigadier General
iqraceworks's Avatar
1981
Rep
3,715
Posts

Drives: 2007 335i
Join Date: Aug 2019
Location: Missouri

iTrader: (0)

If you end up taking a log when it's doing it, please post it up. It should be pretty beast to figure out what's going on.....maybe difficult to figure out why though...
Appreciate 0
      12-22-2020, 02:25 PM   #16
Saif2018
Brigadier General
972
Rep
3,219
Posts

Drives: E90 335i
Join Date: Jan 2019
Location: UK

iTrader: (0)

Quote:
Originally Posted by Wadger View Post
Tha ks for the input guys.

A quick update:
So I flashed v9 map and done a throttle reset.
The issue is still present, however it doesn't seem as bad. I noticed a similar surging when in 1st gear when I was rolling out the car park, but not sure if that's just me moving the pedal a little or being paranoid.
Maybe it's learning still and will fade out, in my haste to get home for dinner I forgot to do a log.
However I've put a reminder on my phone for tomorrow
On a side note, the boost kicks in significantly harder on in the lower rpm's than the v8. Wernt far of parking in the boot of the car I was overtaking

Thanks again to all that have commented
Drive it a couple of days and log to see if it adapts,
Appreciate 0
      12-22-2020, 03:32 PM   #17
Wolf 335
Brigadier General
Wolf 335's Avatar
Canada
2339
Rep
3,538
Posts

Drives: 2007 E92 335i
Join Date: Aug 2012
Location: GTA - Greater Toronto Area

iTrader: (0)

I been dealing with this same issue. I'm stock so I don't think a tune is causing this.
Appreciate 0
      12-22-2020, 09:20 PM   #18
iqraceworks
Brigadier General
iqraceworks's Avatar
1981
Rep
3,715
Posts

Drives: 2007 335i
Join Date: Aug 2019
Location: Missouri

iTrader: (0)

Quote:
Originally Posted by Wolf 335 View Post
I been dealing with this same issue. I'm stock so I don't think a tune is causing this.
Get a log when it's doing it....that will tell you if it's the throttle ocellating, the timing, the fuel, etc,etc....
Appreciate 0
      12-23-2020, 06:04 AM   #19
Saif2018
Brigadier General
972
Rep
3,219
Posts

Drives: E90 335i
Join Date: Jan 2019
Location: UK

iTrader: (0)

Make sure the throttle, boost psi and target etc are all logged guys, on a 3rd gear log, that's DSC fully off, WOT from 2.5k to over 6k, shift into 4th then back off after a few secs.
Appreciate 0
      12-23-2020, 08:07 AM   #20
iqraceworks
Brigadier General
iqraceworks's Avatar
1981
Rep
3,715
Posts

Drives: 2007 335i
Join Date: Aug 2019
Location: Missouri

iTrader: (0)

Quote:
Originally Posted by Saif2018 View Post
Make sure the throttle, boost psi and target etc are all logged guys, on a 3rd gear log, that's DSC fully off, WOT from 2.5k to over 6k, shift into 4th then back off after a few secs.
They are having the issues at light throttle...cruising on the highway etc,etc....

That's when they want to run a log, when it's actually doing the pulsing/ocellating. ....I don't think doing a log at wide open throttle is going to show anything.
Appreciate 0
      12-23-2020, 02:03 PM   #21
Wadger
Enlisted Member
20
Rep
48
Posts

Drives: BMW 335i
Join Date: Mar 2019
Location: Milton Keynes

iTrader: (0)

Good evening all

I done a couple logs on datazap, hopefully the links work.

The weather was really bad on way home today so didn't get much chance, but I got a few logs in that show the issues.
And it definitely seems throttle related to me, it only does it when really light throttle, or cruise control on what I beleive to me a very slight decline. Also the RPM and o2 seem in my inexperienced opinion, reactive to the throttle.
I found it very noticeable today when pulling off or rolling round a roundabout, as I was being super light footed.

But as soon as I fully let off or apply a little more throttle it's absolutely fine.

It defintely seems better when using cruise control, but it felt worse today at really low speed. Maybe due to the fact I never drive like this, due to the weather today.

In a side note, I'm getting some timing corrections while cruising, is this normal?

https://datazap.me/u/ryanw/friday-cruise-control
https://datazap.me/u/ryanw/wed-cruise-control
https://datazap.me/u/ryanw/wed-23-jumpy

Edit: in addition to the work me tioned in my first post, I also had walnut blasting done well under 5k ago.

Thanks to all responding.

Last edited by Wadger; 12-23-2020 at 02:15 PM..
Appreciate 0
      12-23-2020, 03:08 PM   #22
Wolf 335
Brigadier General
Wolf 335's Avatar
Canada
2339
Rep
3,538
Posts

Drives: 2007 E92 335i
Join Date: Aug 2012
Location: GTA - Greater Toronto Area

iTrader: (0)

Quote:
Originally Posted by iqraceworks View Post
Get a log when it's doing it....that will tell you if it's the throttle ocellating, the timing, the fuel, etc,etc....
Do you know if logging possible via ISTA?
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



All times are GMT -5. The time now is 07:32 PM.




e90post
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
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