Darkbmwlord

Well that was an easy fix!

25 posts in this topic

Yesterday the engine started over revving during gear changes, and started really going wild today.:o

 

But when I opened the bonnet to replace the sidelight bulbs for normal ones (highly illegal bright blue ones fitted by last owner), I noticed the maf sensor plug was hanging off...

 

Normal service resumed...:lol:

 

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19 minutes ago, Darkbmwlord said:

Yesterday the engine started over revving during gear changes, and started really going wild today.:o

 

But when I opened the bonnet to replace the sidelight bulbs for normal ones (highly illegal bright blue ones fitted by last owner), I noticed the maf sensor plug was hanging off...

 

Normal service resumed...:lol:

 

 

Wow, that's a bit of a result! If only it was that easy all the time! :lol:

Machinehead likes this

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Was it always like that ?

 

The connector should snap on, unless it's broken there's no way it can just fall off

 

Usually MAFs get disconnected to mask other problems, hopefully you don't have the cold running lumpiness that I never could cure (your sig doesn't say which engine you have)

 

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Well of course, it wasn't that simple...

 

More rough running 10 minutes later, and this time the air duct pipe had come off the maf sensor! So with some dexterous finger work, that was back on. 

 

Then 5 min later, more rough running. The same juddering, missfire, erratic idle when it was wet...except today it is dry.

 

Pulled in at the side of the road, turned it off, counted to 10, restarted, and it drove home perfectly sweetly.

 

I'm getting tired of this car already...:o

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Sounds like you a big branch and give it a damn good thrashing!

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Alternatively I'd get INPA set up and read codes - sounds like there's something wrong. Unless you know why it's running badly you're just guessing.

 

From what you're saying it sounds like someone has had bits apart and not put back together properly. So I'd check everything physically first checking everything is airtight, especially the ducting between MAF and idle control valve.

 

You still don't say which engine you have - that will help people offer correct advice. For example on the petrol engines the CCV is a common source of problems. And of course the MAF may well be faulty.

 

And you can still give it a good thrashing, Basil Fawlty style if it makes you feel better :-)

 

 

 

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Good thrashing guaranteed.

 

I'm waiting for a basic code reader to come, but from what I be read on here I'm leaning towards a coil pack. 

 

But take a look at the attached photographs, and tell me this isn't some kind of bodge! The large square thing under the pipe is hard up against the airfilter housing - and it has fittings that don't seem to have anywhere to bolt onto, plus it is pushing the airfilter housing out of alignment.

 

Looks to me like wrong fitting!

 

Any thoughts?

 

PS - it's a 523 (2.5) manual, bit I can't see how to add that to my profile.

IMG_20170913_161501.jpg

IMG_20170913_161517.jpg

Edited by Darkbmwlord

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Hmm, discovered that this box thingy hanging under the intake hose, after the maf sensor, is a "resonator box." :wacko:

 

I can only think it's been fitted the wrong way round or something, since everything seems to be pushed out of proper placement.

 

Does anyone have a photo of how these components should be correctly fitted together? The Haynes manual images aren't very clear.

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Or look here

newtis.info

Plug your VIN in and browse to the section you want. It's not terribly user friendly, but you'll get the hang of it.

 

Absinthe makes the tart grow fonder

 

 

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17 hours ago, Darkbmwlord said:

PS - it's a 523 (2.5) manual, bit I can't see how to add that to my profile.

 

Just click on the drop down menu at the top right of the screen and select Profile, then click on Edit Profile

 

You can add your car details to the Garage section.

 

Always helpful for others to see what engine and year your car is

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That resonator box should be length ways along the intake pipe behind the MAF; as you look towards the TB

 

It'll slot in (take it out and use a little fairy liquid on the connecting section) and it'll slide in fine. The MAF sensor cable actually slots on to the top of that resonator to keep the cable tidy :) 

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2 minutes ago, d_a_n1979 said:

That resonator box should be length ways along the intake pipe behind the MAF; as you look towards the TB

 

It'll slot in (take it out and use a little fairy liquid on the connecting section) and it'll slide in fine. The MAF sensor cable actually slots on to the top of that resonator to keep the cable tidy :) 

So at the moment it's the wrong way round?:blink:

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Now that's perfect, thank you so much, I shall have to fiddle with mine!

 

Now, I'm waiting for a round to obd connector to come, and then I can try my torque pro app and see if it reveals anything. 

 

I do wish the car had a proper obd plug.:angry:

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may or maybe not connected to your ploblems but search disa valve repair kit and related tails of flap brakeing up

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19 hours ago, supertramp101 said:

may or maybe not connected to your ploblems but search disa valve repair kit and related tails of flap brakeing up

Many thanks for the suggestion, I could be wrong, but doesn't that apply only to 3.0 engines?

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5 hours ago, pt530i said:

OP's car is not a M54, a 523i will be M52 or M52TU - not sure that they have the same setup.

Hmmm, I'm confused, Haynes calls 2.5 as M54! :blink:

IMG_20170915_194557.jpg

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14 minutes ago, d_a_n1979 said:

I'm still confused! The images below are from the above article, and my engine is identical to the one in the picture!

 

The car is called a 523 but the registration document shows it as a 2.5!

 

IMG_20170915_214850.png

IMG_20170915_215030.png

Edited by Darkbmwlord

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Yours is the 523i; so it falls into the 2.0-2.8l M52 category IIRC

 

See below as per the Wiki website:

 


 

Model Engine Power Torque Body style Years
520i M52B20
6-cyl
110 kW (148 hp)
@ 5900 rpm
190 N·m (140 ft·lbf)
@ 4200 rpm
sedan
wagon
1995–1998
  M52TUB20   
6-cyl
110 kW (148 hp)
@ 5900
190 N·m (140 ft·lbf)
@ 3500 rpm
sedan,
wagon
1998–2000
M54B22
6-cyl
125 kW (168 hp)
@ 6100 rpm
210 N·m (150 ft·lbf)
@ 3500 rpm
sedan,
wagon
2000–2003
523i M52B25
6-cyl
125 kW (168 hp)
@ 5500 rpm
245 N·m (181 ft·lbf)
@ 3950 rpm
sedan,
wagon
1995–1998
M52TUB25
6-cyl
125 kW (168 hp)
@ 5500 rpm
245 N·m (181 ft·lbf)
@ 3500 rpm
sedan,
wagon
1998–2000
525i M54B25
6-cyl
141 kW (189 hp)
@ 6000 rpm
245 N·m (181 ft·lbf)
@ 3500 rpm
sedan,
wagon
2000–2003
528i M52B28
6-cyl
142 kW (190 hp)
@ 5300 rpm
280 N·m (210 ft·lbf)
@ 3950 rpm
sedan,
wagon
1995–1998
M52TUB28
6-cyl
142 kW (190 hp)
@ 5500 rpm
280 N·m (210 ft·lbf)
@ 3500 rpm
sedan,
wagon
1998-2001
530i M54B30
6-cyl
170 kW (228 hp)
@ 5900 rpm
300 N·m (220 ft·lbf)
@ 3500 rpm
sedan,
wagon
2000–2003
535i M62B35
V8
173 kW (232 hp)
@ 5700 rpm
320 N·m (240 ft·lbf)
@ 3300 rpm
sedan 1996–1998
M62TUB35
V8
180 kW (241 hp)
@ 5800 rpm
345 N·m (254 ft·lbf)
@ 3800 rpm
sedan 1998–2003
540i M62B44
V8
210 kW (282 hp)
@ 5700 rpm
420 N·m (310 ft·lbf)
@ 3900 rpm
sedan,
wagon
1995–1998
M62TUB44
V8
210 kW (282 hp)
@ 5400 rpm
440 N·m (320 ft·lbf)
@ 3600 rpm
sedan,
wagon
1998–2003
M5 S62B50
V8
294 kW (394 hp)
@ 6600 rpm
500 N·m (370 ft·lbf)
@ 3800 rpm
sedan 1998–2003

 

 

 

However, someone with more knowledge will soon come along and confirm I'm sure :) 

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