2004 BMW Z4 3.0

[parabolica]

thecremeegg said:

The body-coloured strips in the middle of the rear lights - I'm assuming they are just stuck on? As it looks like you've taken yours off? I had a look at removing mine a few weeks ago but they seemed to be well attached and I thought maybe they were screwed/clip or even the plastic underneath wouldn't be the red plastic of the lights. Are they easy enough to remove?

ETA Ah actually I see now you've got de-tango'd rear lights so that probably accounts for it.

[helix402]

Jakg said:

Steering rack bush?

It’ll feel a while let better with the alignment done as the rear toe will be out now as a minimum.

[G600]

parabolica said:

The body-coloured strips in the middle of the rear lights - I'm assuming they are just stuck on? As it looks like you've taken yours off? I had a look at removing mine a few weeks ago but they seemed to be well attached and I thought maybe they were screwed/clip or even the plastic underneath wouldn't be the red plastic of the lights. Are they easy enough to remove?

ETA Ah actually I see now you've got de-tango'd rear lights so that probably accounts for it.

They are held on by foam trim tape.

[parabolica]

Really? I could not get mine off for love nor money; almost like a previous owner had super glued them back on or something. Will maybe look at taking a heat gun to them.

[thecremeegg]

parabolica said:

Really? I could not get mine off for love nor money; almost like a previous owner had super glued them back on or something. Will maybe look at taking a heat gun to them.

Yea they are only held on with tape, at least from the factory. Sounds like your previous owner was a bit over zealous with some glue!

[chrisga]

TwoStrokeNut said:

Lovely!

Really like the colour. It'll look a lot better with silver wheels though, as the black does clash a bit.

It'll ride much better on non-runflats. Also it'll probably need some new shocks and bushes, rear RTAB in particular.

Enjoy!

Might look like this with silver wheels.... Got our 2.5 in April and enjoying it so far. As per the rest of this thread the steering can be a bit vague though and it also tramlines. It's on nearly new p zero run flats at the moment. Same as the OP feel loathe to throw away decent tyres but will probably try normal when time comes to replace.

[Sticks.]

I kept my rfts for quite a while. Although getting rid is an improvement, it's nothing like an E46 on mismatched tyres.

Not just tramlining though, the car felt less unsettled my small bumps, more planted, almost lower. In short, like you'd have expected it to.

[Jakg]

Welcome to my not-a-project car that I'm definitely not modifying.

Fitted a dashcam. Went for the lazy option and wired it into the wiring for the rain sensor as it's on an ignition live.



Took the DISA valve out and cleaned it up, but hasn't made a difference to performance. I think with all the use it's got that it's loosened up a bit, but still doesn't quite feel 230HP. VANOS is a job for the winter I think.

Gearknob was in a state so got a new one. Couldn't get a ZHP one (OE BMW sport one) from a dealer in the UK, but found a slightly cheaper one on eBay from Bulgaria. Turned up in a BMW box, but was a fake (incorrect weight). Seller said they had no idea, but immediately sent a refund without checking anything... suspicious. Fitted it anyway and it's ok. Will probably get the real deal later.



Bought a strut brace off eBay as it was cheap. When it turned up it was suspiciously light (<3KG). I had a look at the sellers other items and they've since relisted more of them with a description of "no idea what car this fits". Good start.



Unsurprisingly, doesn't fit!

Engine is nothing special to look at, but having only owned transverse engined cars every time I open the bonnet I'm immediately reminded how long it is!

Replaced the broken exhaust mount that I noticed the other day, only to realise there's actually two for the backbox. And the other is broken. So that's another job. At least they are only £9.



While I had it jacked up I also fitted some Powerflex rear anti roll bar bushes, and removed the clutch delay valve.

Had the alignment done and it's improved the handling quite a bit.



Unfortunately the garage have used the wrong settings (sport vs non-sport suspension). They also said that the front camber isn't adjustable (or more precisely, is adjustable but never works). Having looked it up online you just drop a pin out and move the strut tops in the oversized holes. Not sure how that can "not work".

Tramlining has reduced, but on the other hand the stiffer bushes have made it sharper which makes it more apparent. Will spend some more time driving it and think about what next to improve it. I also noticed that three of the tyres are Bridgestone Runflats, and one is a Landsail non-runflat (don't know how I missed that!) which definitely won't be helping!

Ran the car through one of those VIN decoders and it turns out it's got quite a few optional extras.

The good news is that it's a got a fancy 10-speaker stereo system.

The bad news is that it's got a fancy 10-speaker stereo system, with a cutting edge digital link from the headunit to the amplifier in the boot... in 2004.

Tried swapping out the headunit but while a new one powers up, no sound comes out of the speakers as it's not sending the output to the amplifier via KBUS.



The only solution appears to be to replace the amplifier in the boot with an aftermarket one, and do the crossovers for each speaker yourself.

On the plus side, at least the amplifier is near the battery.



2 tanks in and it's averaging 32MPG which isn't too bad.

Edited by Jakg on Wednesday 24th August 10:03

[TwoStrokeNut]

A chap on the z4 forum did some audio spectrum analysis on the carver unit.

https://z4-forum.com/forum/viewtopic.php?f=2&t...

Try his settings. My sound went from pretty terrible to acceptable using those.

[Jakg]

TwoStrokeNut said:

A chap on the z4 forum did some audio spectrum analysis on the carver unit.

https://z4-forum.com/forum/viewtopic.php?f=2&t...

Try his settings. My sound went from pretty terrible to acceptable using those.

With the basic "business" head unit, you can't adjust those settings unfortunately.

[Mr Tidy]

OP, you're doing well considering you weren't going to modify it!

I bought a genuine ZHP gear-knob for my Z4 last year from Cotswold BMW and it's a huge improvement over the original, so worth looking out for one.

Looking forward to seeing what is next on your list!

[TwoStrokeNut]

Jakg said:

With the basic "business" head unit, you can't adjust those settings unfortunately.

Hmm, that's weird. What DSP settings can you change?

Without the Nav screen, I think I would junk all of the factory kit and install an aftermarket headunit and amp in the stock location. Get a circuit diagram and you should be able to reuse some of the wiring.

[5harp3y]

better off swapping in a Pro Headunit.

or get the right connector from Connect2 (Recently did this to fit an aftermarket HU to my wifes 1 series)

[TwoStrokeNut]

With the Pro headunit, you're still left without Nav, DAB, no bluetooth audio, a crappy sound and can only play MP3s from a CD, if you're lucky.

..plus difficulty upgrading the amp / speakers.

[Jakg]

5harp3y said:

or get the right connector from Connect2 (Recently did this to fit an aftermarket HU to my wifes 1 series)

There is no such adaptor to make this work - the amp requires a digital signal which no aftermarket HU provides

TwoStrokeNut said:

Hmm, that's weird. What DSP settings can you change?

Without the Nav screen, I think I would junk all of the factory kit and install an aftermarket headunit and amp in the stock location. Get a circuit diagram and you should be able to reuse some of the wiring.

You can select three DSP modes, and that's it!

I'm leaning more towards a new amp..

[xjay1337]

Jakg said:

helix402 said:

Have you had the wheel alignment (4 wheel) done with the new bushes?

Not yet. That's the other thing on the list. The plan was to wait until the suspension was "done" before I did it.

Jez m said:

New steering rack bushes and a full alignment sorted out my old Z4's 'nervous' and darty feel. Mine was on non-run flats too.. that made the biggest difference of all to the handling.

Steering rack bush?

I would 100% get the alignment done now rather than in a few weeks etc.

When I changed the bushes on my old Scirocco I had 30 degrees of total toe.
The old ones were not broken, and the new ones were Powerflex.

Edit: Just seen you had already had it done - the thread didn't load properly yesterday!!!!

Edited by xjay1337 on Tuesday 7th August 09:47

[TwoStrokeNut]

Jakg said:

ou can select three DSP modes, and that's it!

I'm leaning more towards a new amp..

For me, I found the sound when set flat to have way too much woolly bass, harsh treble and it was hard to hear the voice / midrange.

Part of the problem is the auto loudness that is applied to the low end when the auto volume kicks in. Turning the auto volume increase down helps with this.

Then maybe turn the bass down a bit and the treble which should leave the mids somewhat.

...or just maybe that's just rolling it in glitter

Edited by TwoStrokeNut on Tuesday 7th August 17:21

[Jakg]

Jakg said:

Unfortunately the garage have used the wrong settings (sport vs non-sport suspension). They also said that the front camber isn't adjustable (or more precisely, is adjustable but never works). Having looked it up online you just drop a pin out and move the strut tops in the oversized holes. Not sure how that can "not work".

Took the car back, and was told I was "very lucky" as the camber adjusted which is apparently unusual.

They were however insistent that the settings were the same between sport vs non-sport suspension, when I brought up AutoData they dismissed this as Hunter's settings are direct from the manufacturer.

Having done some more research, definitely not the same settings - but it turns out that they have aligned it to the correct ones anyway - i.e. they simply didn't notice the settings had changed - you can see the difference between allowed camber ranges between the two printouts.

The fact they didn't spot this, or that a car that had an alignment a week ago was suddenly red all over I have no idea. Not used them before for alignment and not sure if I would again - shame as they are local and have the proper Hunter gear.



Working through the service history and the last recorded pollen filter was several years ago. When I pulled it out it's clearly been done recently - I changed it anyway as I had it out but it appears the cars been looked after properly.



In the middle of changing the VANOS seals at the moment... not a fun job on an E46, let alone on a car with a much smaller engine bay.

[Jakg]

Jakg said:

In the middle of changing the VANOS seals at the moment... not a fun job on an E46, let alone on a car with a much smaller engine bay.

The car seems to be getting through oil quite quickly. From underneath I could see oil on the engine so at least it's not burning it, although through the vents with the blowers on you could smell burning oil which points to oil leaking onto the exhaust and burning off there.

The car seems down on power (but coming from a turbo diesel with similar power, but more weight, makes it difficult to tell!) and a common cause is the seals on the VANOS unit wearing out (VANOS = BMW's variable valve timing system). The OE seals are made from the "wrong" kind of rubber and as such don't last.

Removing the VANOS unit requires replacing the valve cover gasket which is the most common source of oil leaks on the M54 engine so I thought I'd kill two birds with one stone.

Although I only need a couple of seals for the VANOS unit, I bought a complete kit from X8R that includes various other seals and gaskets that get disturbed along the way. Not cheap at £80, but very comprehensive.

VANOS removal is well-trodden for the E46 but on the Z4 it's significantly harder as there's just no room to work in.



A panel comes off the top of the radiator to give a little access to the front of the engine to get to some of the bolts. I managed to do it without removing the fan, but cut my hands to bits in the process.



Covers off



Coils and wiring out of the way



Valve cover off





The VANOS unit are the two spheres to the right of the cam chain.

The space between the front of the engine and the bulkhead was so small that I couldn't even fit a ratchet in at some points. It's mounted using studs and one stud was slightly too long such that the VANOS unit won't clear it before getting stuck on the bulkhead - ended up having to move the unit forward and then unwind the stud using molegrips.

In addition the housing for the coolant temp sensor fouls the VANOS unit so that has to come out too, meaning some coolant is lost.

Lots of effort later



Dismantled the VANOS unit and replaced the piston seals. The existing seals were rock-hard.



Put it all back together, but when topping up the coolant I noticed it was a nice brown-rust colour. Don't think it's been changed in a while, will have to add to the list.



It's too early to say if it's fixed my oil leak, but having replaced the valve cover gasket I don't appear to have introduced any new major oil leaks which I suppose is a success in itself having never tackled anything "engine-y" like this before.

Performance seems the same, though - the seals take some time to "bed in" but perhaps I need to adjust my perception too.

"Bedding in the seals" was a good excuse to take it out, though.

[parabolica]

How long start to finish did the VANOS job take OP? I've been thinking about doing mine at some point but wasn't sure how much time to budget for.