Flat spot and pinking cured

UK forum for general and technical discussion about the Z3 roadster

Moderator: Gazza

Post Reply
User avatar
Gordon13
Joined: Tue 16 Sep, 2014 19:45
Posts: 58

  Z3 roadster 2.2i

Flat spot and pinking cured

Post by Gordon13 » Sat 18 Jul, 2015 21:42

After ages looking and trying to get my head around this, today i decided to remove the intake manifold and check every thing.

There is a lot of info on the internet regarding pinking and flat spots but nothing i found pointed to my discovery.

Hidden at the back of the manifold, behind the dip stick area are three ports into the manifold, two small an one larger and on mine, were all blanked off or should have been.

The larger of the blanks was in place but badly perished and obviously leaking air. This would result in unmetered air giving a weak mixture resulting in pinking and flat spot.

A temporary repair was carried out for now.

The interesting thing is that the result wasnt instant. The pinking went immediately but the flat spot took a while to improve, 30-40 miles.

i guess that is to do with the 'learning' process of the ecu ?

Image

Image

Image
Image

User avatar
Brian H
Joined: Tue 16 Dec, 2008 19:55
Posts: 2503

  Z3 roadster 3.0i

Re: Flat spot and pinking cured

Post by Brian H » Sun 19 Jul, 2015 10:08

^^^good info, perished rubber hoses etc. are becoming a common source of problems.

User avatar
Southernboy
Joined: Thu 07 Oct, 2010 13:39
Posts: 6312

  Z3 roadster 3.0i
Location: Johannesburg

Re: Flat spot and pinking cured

Post by Southernboy » Sun 19 Jul, 2015 12:12

Excellent revelation ! the info should be included into the Knowledge base as a "check here first before replacing MAF'S / Sensors etc".... A small item like that could go undetected and cost a bomb on other possibilities without getting to the root of the problem. :rtm:
"Normal is overrated"
Image

Z3 Upgrades and Additions

TWO
Joined: Tue 05 Apr, 2011 23:04
Posts: 170

  Z3 roadster 2.2i
Location: Chelmsford

Re: Flat spot and pinking cured

Post by TWO » Sun 19 Jul, 2015 18:48

Hi Gordon13

I've just checked mine and found a very similar hair line split :( ..........I owe you a pint :)

Have you had a chance to find out the OEM part number and the price yet?

Many thanks for taking the trouble to make us all aware :cheers
Image

Vic-Z3
Joined: Fri 11 Jun, 2010 20:28
Posts: 915

  Z3 roadster 2.2i
Location: Redditch
Contact:

Re: Flat spot and pinking cured

Post by Vic-Z3 » Sun 19 Jul, 2015 19:22

Mine was exactly the same, full length crack and it was just about holding onto the peg.

A quick and temporary fix with black insulation tape wrapped round several times and
it is a very snug fit back on.

:thumb:
----------------- BMW Z3 Das Beste Auto -----------------

Mein altes Auto riecht nach Nudeln, hat dieses Auto eine Wurst Geruch.

User avatar
Gordon13
Joined: Tue 16 Sep, 2014 19:45
Posts: 58

  Z3 roadster 2.2i

Re: Flat spot and pinking cured

Post by Gordon13 » Sun 19 Jul, 2015 20:32

Glad im not the only one and its a pleasure to be of some help

part number is 11611727176 although this may have been superseded, haven't tried ordering one yet.

I'm hoping that the scenario will be thus :

extra unmetered air results in a weak mixture and piking
The ecu 'sees' this from the ping sensors and try's to rectify it by retarding the ignition and altering the cam timing.
So, if the pinkning was still evident when running with the air leak then the ecu must have done all it could to eliminate it and be running as de-tuned as possible, therefore as it relearns the current parameters I should see a marked increase in perfomance :D

Thats how I think it works any way !!
Image

User avatar
BonBon
Joined: Tue 08 Jan, 2008 21:10
Posts: 1175

  Z3 roadster 1.9

Re: Flat spot and pinking cured

Post by BonBon » Sun 19 Jul, 2015 21:13

Not clear - but in contrast to the pic in RealOEM the manifold on my M44 looks completely different and does not have the same structure with the nipples underneath and PN#7
http://www.realoem.com/bmw/enUS/showpar ... Id=13_1733
Image

User avatar
Gordon13
Joined: Tue 16 Sep, 2014 19:45
Posts: 58

  Z3 roadster 2.2i

Re: Flat spot and pinking cured

Post by Gordon13 » Mon 20 Jul, 2015 07:08

Sorry, should have made it clear in the first post, this is on an m54 .
Image

User avatar
BonBon
Joined: Tue 08 Jan, 2008 21:10
Posts: 1175

  Z3 roadster 1.9

Re: Flat spot and pinking cured

Post by BonBon » Mon 20 Jul, 2015 08:00

No problem with you. Realoem shows that the M44 also has that bung - but in reality I don't.

User avatar
Tufarlian
Joined: Sat 14 Mar, 2009 20:21
Posts: 267

  Z3 roadster 3.0i
Location: Cheshire
Contact:

Re: Flat spot and pinking cured

Post by Tufarlian » Mon 20 Jul, 2015 11:20

Interesting thread. Thanks for sharing this. Just checked mine and it is split.

Insulating tape ok for now.

I think I've found the part on RealOEM but it's greyed out. Possibly no longer available?

I think it's number 9 on this diagram.

http://www.realoem.com/bmw/enUS/showpar ... Id=11_6225

Mark

User avatar
BladeRunner919
Joined: Fri 17 Feb, 2012 20:18
Posts: 2221

  Z3 roadster 1.9

Re: Flat spot and pinking cured

Post by BladeRunner919 » Mon 20 Jul, 2015 12:31

If it's greyed out, than means (in theory) it doesn't apply to your car. Real Oem uses the same diagram for different applications/markets, but only lists the components that are relevant to your chassis number.

User avatar
Tufarlian
Joined: Sat 14 Mar, 2009 20:21
Posts: 267

  Z3 roadster 3.0i
Location: Cheshire
Contact:

Re: Flat spot and pinking cured

Post by Tufarlian » Mon 20 Jul, 2015 16:54

BladeRunner919 wrote:If it's greyed out, than means (in theory) it doesn't apply to your car. Real Oem uses the same diagram for different applications/markets, but only lists the components that are relevant to your chassis number.

"in theory" :-)

The link is from a search based in my car's chassis number and I can assure you that the split rubber bung is definitely on the car.

I removed it, taped it up and put it back this morning. :)

If anyone has the part number can you let me know please?

Cheers
Mark

User avatar
Zed Free
Joined: Mon 12 Nov, 2012 20:23
Posts: 69

  Z3 roadster 2.2i

Re: Flat spot and pinking cured

Post by Zed Free » Mon 20 Jul, 2015 17:24

Try items 15 and 17 on this link

http://bmwfans.info/parts-catalog/Z3-Ro ... ld_system/

Which gives 11 61 1 727 176 for the big one 7mm and 11 61 1 437 560 for the small one 3.5mm.
Zed Free. - 2.2 Titanium Edition.
Image

User avatar
Tufarlian
Joined: Sat 14 Mar, 2009 20:21
Posts: 267

  Z3 roadster 3.0i
Location: Cheshire
Contact:

Re: Flat spot and pinking cured

Post by Tufarlian » Mon 20 Jul, 2015 17:44

Thansk

TWO
Joined: Tue 05 Apr, 2011 23:04
Posts: 170

  Z3 roadster 2.2i
Location: Chelmsford

Re: Flat spot and pinking cured

Post by TWO » Mon 20 Jul, 2015 20:30

I've just replaced the old cap (see below, cracked both sides :shock: ) with new ( Pt No 11611727176 @ £1.45, BMW OEM) plus a wipe over with Gummi Pflege for good luck.......2 minutes in total :)

I'll be out for a test drive tomorrow :sunny

Image

Image
Image

Brian4
Joined: Mon 19 Dec, 2011 19:02
Posts: 536

  Z3 roadster 3.0i
Location: Hinckley

Re: Flat spot and pinking cured

Post by Brian4 » Tue 21 Jul, 2015 18:00

Thanks TWO for the part number and Gordon for highlighting this. Checked mine last night and it looked just like yours TWO. Until I get one ordered I used superglue to join the splits together and the wrapped in tape, made a much snugger fit going back on than when it came off. In fact it came off that easy I dropped it and must have bounced up of the floor and ledged between the sump and chassis brace. Took me ages to find it.
Brian
3.0I Topaz Blue


2000 E36/7 Z3 3.0i
2016 F31 335d
2015 F21 118i

Post Reply

Who is online

Users browsing this forum: pingu and 3 guests