Mike’s Z3 - Fitting Retro Aircon + Cruise etc Project

MickyG

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Nov 9, 2025
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28
Model of Z
3
That is not exactly true. There were at least two (possibly more) changes to the DME and other modules over the build period, as I have learned to my cost.
From 2000-on there was 'canbus' added to provide 'modern' electronics to quite a few wiring functions.

But it does seem that all of the 'normal' electrical stuff is common to all and the general looms are generic.
Interesting.
My donor is/was a 2001 M54 2.2.
I’ve encountered changed plug styles on the Aircon - hopefully nothing more! (Though I won’t know until it is pressurised to allow the compressor and fan to kick in).
The M seats seem to have a different wiring set up (not just plugs) but because they are heated I’d like to add that functionality to my car; I am hoping I can swap the seats onto my own bases and then wire up the heated elements separately.
This probably concerns me more than the Aircon as a project.
But again Google and this forum are my friends🙂 and I’ll get there.
 

Nodzed

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British Zeds
M Power
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Forest of Dean, Gloucestershire, England
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Z3M Imola and Z4 (e89)
Hi Ian
Lucky you with factory fitted options🤗
Cruise was very easy to fit: Aircon will be much less so!!!!!!!!
I’ve managed to get hold of a cheap Z3 2.2 Special Sapphire Edition with Blue/Black M seats (are they exactly the same as the M - does anyone know for certain?). I do know they are much better than my standard seats for support and comfort and will go with my Atlanta Blue car.
The deal clincher was it having Aircon, and a set of Z3 factory staggered Style 32 wheels (my preferred option on a widebody 2.8).
I’ve removed the Aircon already - and am pausing, swallowing hard, and summoning up the courage to tear my beautifully trimmed interior out to be able to swap it over!😳
If you have M sport seats they are not the same as M seats.
 

Pond

Zorg Guru (III)
British Zeds
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Location
Spaldingski, Lincs
Model of Z
3 litre Z3 pretending to be Italian exotica. Two previous E89 Z4s.
My donor is/was a 2001 M54 2.2.
I’ve encountered changed plug styles on the Aircon - hopefully nothing more! (Though I won’t know until it is pressurised to allow the compressor and fan to kick in).
The M seats seem to have a different wiring set up (not just plugs) but because they are heated I’d like to add that functionality to my car; I am hoping I can swap the seats onto my own bases and then wire up the heated elements separately.
So your 'car' is a 1999 M52 2.8 and the 'donor' is a 2001 M54?
From what I have gathered if a Z3 has ASC (auto stability control) it will be be on the analogue wiring; if it has DSC (dynamic stability control) it will be on the newer 'digital' wiring loom with a different DME (and ECU I think). I may be wrong but it does seem to be an easy way of telling.

I have full 2000 year and 2001 year wiring diagrams on PDF if you need them emailing. 95% are the same for each but the 5% are always the ones you need!
 

MickyG

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Joined
Nov 9, 2025
Points
28
Model of Z
3
So your 'car' is a 1999 M52 2.8 and the 'donor' is a 2001 M54?
From what I have gathered if a Z3 has ASC (auto stability control) it will be be on the analogue wiring; if it has DSC (dynamic stability control) it will be on the newer 'digital' wiring loom with a different DME (and ECU I think). I may be wrong but it does seem to be an easy way of telling.

I have full 2000 year and 2001 year wiring diagrams on PDF if you need them emailing. 95% are the same for each but the 5% are always the ones you need!
Yes please to the wiring diagrams: particularly the seats.
Do you have the earlier 99 diagrams too?


Many thanks
 
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Pond

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3 litre Z3 pretending to be Italian exotica. Two previous E89 Z4s.
Yes please to the wiring diagrams: particularly the seats.
Do you have the earlier 99 diagrams too?
Many thanks
I don't have 1999. It may not be the best idea to put your email address on a public website. Anyone can access this site. I have made a note of the address if you want to edit.
 

MickyG

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Nov 9, 2025
Points
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Model of Z
3
If you have M sport seats they are not the same as M seats.
This is a subject I would like to understand in more detail.
BMW use the M badge quite loosely.
In terms of seats I have physically seen 3, but possibly 4 different specifications.
Standard
Sport
M Seats - as in Z3M. } =
Sapphire Edition “M Sports seats” } =

My uncertainty lies around the Z3 2.2 Sapphire Edition.
This was a run out edition usually offered by BMW with a 2.2 engine with an option for a Z3M stylised interior with M Sports seats and colour coded door cards, handbrake, gear lever gaiter and steering wheel.
These seats are not Sports seats: the bolster designs and seam stitching matches the Z3M.
But does that make them the same?

This is my Sapphire Edition interior:

IMG_7138.jpeg


IMG_7110.jpeg


The seat base stitching and upper bolster design are, I believe, the same as Z3M seats.

Nodzed, are you saying these seats are not “The same” as those in a Z3M?
 
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MickyG

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Joined
Nov 9, 2025
Points
28
Model of Z
3
A quick test fit of the condenser and pipework confirms they all fit.

IMG_7425.jpeg

Whilst researching this project it’s become apparent the driers are non re-usable as once the system is open to air they quickly saturate, so I’ll order a new one along with new seals throughout the system.
Also I’ve noticed one of the aluminium connections between the condenser and pipe to the drier at the front of the car is badly corroded. I’ve cleaned them up, but if the joint leaks, the cost of de-gas and re-gas means I’m better off buying a new condenser and short pipe from one of the OEM suppliers to BMW.
 

Pond

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Location
Spaldingski, Lincs
Model of Z
3 litre Z3 pretending to be Italian exotica. Two previous E89 Z4s.
Yes drier/receivers should be changed if exposed to the air for more than a few minutes.
The most important thing to remember with a refrigeration system is that moisture is the enemy. Air contains a lot of moisture, so keeping air out as much as possible is a wise move. When you have the system tested and filled with R134a make sure you ask whoever does it to give it a very good 'vac' (evacuation). Even the smallest amount of moisture can cause huge problems.

I would offer to do it for you but I don't have the equipment anymore as I 'hung up my gauges' a good few years ago now.
 

MickyG

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Joined
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Points
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Model of Z
3
Yes drier/receivers should be changed if exposed to the air for more than a few minutes.
The most important thing to remember with a refrigeration system is that moisture is the enemy. Air contains a lot of moisture, so keeping air out as much as possible is a wise move. When you have the system tested and filled with R134a make sure you ask whoever does it to give it a very good 'vac' (evacuation). Even the smallest amount of moisture can cause huge problems.

I would offer to do it for you but I don't have the equipment anymore as I 'hung up my gauges' a good few years ago now.
Is there anyone local that you could recommend when I’m ready ?
(I’ve ordered a new drier, condenser and front high pressure pipe, due to joint corrosion, and a complete set of O-rings).
 

Pond

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British Zeds
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Spaldingski, Lincs
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3 litre Z3 pretending to be Italian exotica. Two previous E89 Z4s.
Is there anyone local that you could recommend when I’m ready ?
(I’ve ordered a new drier, condenser and front high pressure pipe, due to joint corrosion, and a complete set of O-rings).
No sorry. Everyone I know is based a long way away. I moved up here from Bucks and my work is still based down there.
TBH I wouldn't recommend anyone who works for me anymore anyway; most of them are useless!!
 

AntStark

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2002 3.0 Sport
This is a subject I would like to understand in more detail.
BMW use the M badge quite loosely.
In terms of seats I have physically seen 3, but possibly 4 different specifications.
Standard
Sport
M Seats - as in Z3M. } =
Sapphire Edition “M Sports seats” } =

My uncertainty lies around the Z3 2.2 Sapphire Edition.
This was a run out edition usually offered by BMW with a 2.2 engine with an option for a Z3M stylised interior with M Sports seats and colour coded door cards, handbrake, gear lever gaiter and steering wheel.
These seats are not Sports seats: the bolster designs and seam stitching matches the Z3M.
But does that make them the same?

This is my Sapphire Edition interior:

View attachment 352669

View attachment 352663

The seat base stitching and upper bolster design are, I believe, the same as Z3M seats.

Nodzed, are you saying these seats are not “The same” as those in a Z3M?
You have M seats mate
 

MickyG

Dedicated Member
Joined
Nov 9, 2025
Points
28
Model of Z
3
Whilst waiting for my new condenser and drier to arrive I’ve been selling a few bits from my donor car.
This morning the Roll Hoops went to a guy with a Z3 “Cobra”. During the process I am reasonably sure, but would like confirmation from those who know, that I do in fact have a hard top fitting kit.
IMG_7456.jpeg


IMG_7454.jpeg


IMG_7451.jpeg


IMG_7455.jpeg


Assuming that it is the hard top fitting kit, and that I have all the fixing and heated rear screen switch, is there anyone looking for one of these kits here on the forum?
I know some people are asking crazy figures for such kits, but I am only looking to get back my costs of my donor car, so someone will get a good deal.
 

spurs fan in a coupe

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Whilst waiting for my new condenser and drier to arrive I’ve been selling a few bits from my donor car.
This morning the Roll Hoops went to a guy with a Z3 “Cobra”. During the process I am reasonably sure, but would like confirmation from those who know, that I do in fact have a hard top fitting kit.View attachment 352989

View attachment 352991

View attachment 352993

View attachment 352995

Assuming that it is the hard top fitting kit, and that I have all the fixing and heated rear screen switch, is there anyone looking for one of these kits here on the forum?
I know some people are asking crazy figures for such kits, but I am only looking to get back my costs of my donor car, so someone will get a good deal.
Yes that’s a hard top kit, looks complete - you just need to grab the 2 torx bolts out from the upper windscreen surround holes - roughly above the sun visors with the roof down you can push them out.
 

MickyG

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Joined
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Model of Z
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Excellent. Thanks for the prompt response.
I’ll see if the torx bolt are there too?

Anyone looking for a complete kit?
 

MickyG

Dedicated Member
Joined
Nov 9, 2025
Points
28
Model of Z
3
“ You Pay For Your Learning, Son”

…….. is a very wise saying passed down in our family from a canny Scotsman commenting on a motorist trying desperately to free his car from a sandy beach as the tide flowed in.

… it has just caught up with me again today🥴

I excitedly opened my Autodoc parcel containing condenser, drier and high pressure hose.

I’d ordered a Mahle condenser and drier believing them to be a “good brand”.
Sadly I would not recommend either component.
The condenser top brackets are much wider than the OEM item making installation more difficult and are very flimsy, not allowing them to be tightened with twisting them unintentionally - but I got there in the end.

The receiver drier does not fit my 2.2 pipework, despite AUTODOC confirming it would.

Subsequent research has shown me that there are two differing pipe connection fittings.
“Straight sided” and “Step shoulders”.
IMG_7501.jpeg


This is the straight sided version I have from my 2.2 (it’s the same as the 2.8, and Z3M)

IMG_7506.jpeg
IMG_7502.jpeg


This is the shouldered version I received from AUTODOC
IMG_7508.jpeg

my straight pipe connections will not fit - but of course I have tried without realising there was a difference, so I can no longer send it back.

I’ve now ordered a straight sided version…… with “You pay for your learning, Son” still ringing in my ears🥴

On a positive note, the condenser and pump pipework is connected, and for future reference, it appears my 2.8 now has completely standard air conditioning components for a 2.8 Z3.
 

Pond

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British Zeds
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Location
Spaldingski, Lincs
Model of Z
3 litre Z3 pretending to be Italian exotica. Two previous E89 Z4s.
Mike,
It is highly advisable to tape over any exposed a/c pipe ends and fitting holes until the minute you want to fit them. Keeping as much air/ moisture out as possible is worth the little extra effort
 

MickyG

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Joined
Nov 9, 2025
Points
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Model of Z
3
Finally buttoned up the Aircon pipework this afternoon after receiving the correct specification drier (with straight shoulder connections).
IMG_7563.jpeg


All that remains is to sort out a working Aircon fan, as the one from the donor doesn’t rotate freely - I’m guessing it is the brushes. I’ve located an alternative from an other Z3 enthusiast, but will have to wait for a suitable opportunity to view/collect it. However it is a very quick stand alone item to install, so I can now concentrate on re-installing the dash & centre console.

Mission creep has inevitably set in now though!

The donor Z3M seats are heated, so I want to add the switches in the front centre centre console, along with the power hood switch and Aircon switch. This means the ASC switch needs to be relocated into the rear console’s (and requires extended wires).
I also quite like the facelift centre console with its analogue clock and silver finish with chrome rings, so that’s going in too. It does however leave me with an other conundrum: what to do with the original On Board Computer digital clock and display.

I will also take the opportunity to install new bushes in the power seat bases to avoid the inevitable “seat rock”.

So still plenty to do and play and with!🤗
 
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Stevo7682

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Maybole , South Ayrshire
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Z3 Individual Dakar / Orinoco Individual
This is a subject I would like to understand in more detail.
BMW use the M badge quite loosely.
In terms of seats I have physically seen 3, but possibly 4 different specifications.
Standard
Sport
M Seats - as in Z3M. } =
Sapphire Edition “M Sports seats” } =

My uncertainty lies around the Z3 2.2 Sapphire Edition.
This was a run out edition usually offered by BMW with a 2.2 engine with an option for a Z3M stylised interior with M Sports seats and colour coded door cards, handbrake, gear lever gaiter and steering wheel.
These seats are not Sports seats: the bolster designs and seam stitching matches the Z3M.
But does that make them the same?

This is my Sapphire Edition interior:

View attachment 352669

View attachment 352663

The seat base stitching and upper bolster design are, I believe, the same as Z3M seats.

Nodzed, are you saying these seats are not “The same” as those in a Z3M?
They are M seats same as in a z3m.

To my knowledge if you dont take into consideration what the seats are covered in.
Then there is 4 seat design.
Standard seat
2 varients low and high back
Then
Sports seats
And
M seats.

Easiest way to tell a sport seat and and M seats apart is M seats have additional shoulder bolster that are not fitted to the Sports seats.
Screenshot_20251208_193008_Photo Editor.jpg

They also have larger side bolster , different stitching and usually different leather
Sports seats usually oregon or chameleon leather but M seats usually nappa leather.

Stephen.
 
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