project 2004 BMW Z4 2.2 - De-snagging

[SiC]

30 minutes ago, cort16 said:

How long is the MOT? I would see the airbag issue as a next MOT problem and build up to dealing with it then.

9th June! Less than 57 days left.

So I need to get working on it as no doubt that will come around quickly and this will be a big MOT show stopper. 

[SiC]

This evening I had a few hours to put these new rear pads in. 

Apart from the E320, pretty much every car I've bought in the last year has its rear or front end in the air soon after I've bought it. 🤣

 

This is the offending side.

There certainly isn't much meat left on this pad! (More in a moment)

 

Slider pins are covered in white grease. Now I'm never sure if you should grease these pins? I thought you did but I have read that BMW say not to.

Pulled it all off and inspected it all.

Disc looked reasonable. It's had some heat through it but no massive scoring that I could see.

Slider pins were covered in grease. The bottom one I'd already started cleaning up (then remembered to take a photo) hence why it has less on it in this picture.

Piston doesn't look too bad under the boot from what I can see?

Carrier was crusty and filthy. I cleaned this up and greased the pad touch points. 

Piston went in but did take a fair bit of force with the spreader.

Now those pads...

Bottom is the inner and top is the outer.

I don't know what the pros think but my view is that I bloody luckily got away with not damaging the disc! There is a wafer thin amount of pad material left and the top just started kissing the raised lip of the disc.

I reckon the disc will be perfectly okay to reuse and isn't damaged? Incredibly close to doing so though.

I'd rather not change it if I don't have to, as they're not that old. Doesn't feel to have any high or low spots either.

Bloody lucky though!

The other side has loads of meat on the pads still. I didn't take pictures as I wanted to get it finished. The caliper piston and carrier were actually in far worse a state than the passenger side. Yet it span more freely. 🤷‍♂️

I put it all back together with new pads, cleaned up sliders and carrier. After pressing the brake pedal, the drivers side rear rubs ever so slightly but you get a tiny bit of spin after letting go. The passenger side however is really stiff and you need the wheel on for enough leverage to turn it. 

To me I definitely need a new passenger rear caliper. But tbh I think I might need both and be done with it. My thought is also that the drivers side might either be or become soon seized if the other side already has. 

I should also say while I think about it, I did try some hard braking on the way back. It didn't brake straight and true. More squirrelly and needed a fair bit of correction to keep it braking straight. Hopefully two new rear calipers will sort it all out properly.

Also noticed the passenger side has an older (rusty) Bilsten damper while the drivers side had a shinier newer looking Sachs damper. Tempting to lob a new one on that passenger side to have a matching new(ish) pair. Depends how much they are though.

[SiC]

Okay so I've been doing a bit of double checking on caliper part numbers. The caliper pair I linked earlier are not for this. Those are bigger and only fit the 2.5si and 3.0i/3.0si. This 2.2 has the same as the 2.0 and 2.5i, which are more expensive.

I think this is correct based on the part numbers on RealOEM:

https://www.partsinmotion.co.uk/car-parts/braking/calipers/nk-2115207-brake-caliper-2115207-detail

Unfortunately eBay doesn't have any offers on with parts in motion right now. At nearly £50 I probably will only buy that left side as I can't justify doing the right as well at that price, when it appears okay at the moment. Maybe I'll regret that decision...

[JakeT]

Could you see if you can find a rear caliper for an E46 316/318i? There should still be plenty being broken, so a cheap caliper should see it right. That’s what I ended up doing after having so many ones go sticky over the years of owning E46s.

[SiC]

6 hours ago, JakeT said:

Could you see if you can find a rear caliper for an E46 316/318i? There should still be plenty being broken, so a cheap caliper should see it right. That’s what I ended up doing after having so many ones go sticky over the years of owning E46s.

It's weird. If you search eBay for a Z4 caliper or 316i you get the first link I put above with the cheaper calipers. However if you check the listed part number it doesn't match up with realoem. 

I've ordered the more expensive NK caliper which hopefully should be correct. 🤞 

Hopefully the flexi pipe isn't a problem as that might be a bigger job. Ferrules are rusted to hell and no doubt round off while possibly breaking the hard lines. 

[JakeT]

Ah right, okay. One option is there’s an E46 breaker called Nick Jupp. He’s the E46 whisperer in many circles and may have a pair of calipers available. Much cheaper than new ones, too.

[tooSavvy]

I still can't get past my own 'smokey mountain high' front calipers 😵‍💫....

Both locking 'out', almost within weeks, and Fleebay scrappers [from older m/y] sourced around £25....

Working GR9 🤪

🚙💨

[SiC]

Slapped the new nearside caliper on. Quality is definitely not as good but it fits and seems to work fine. Drag feels the same on both sides.

Bled the rear brakes on both sides for good luck. Fluid seemed pretty clean - I think because the rear lines have been replaced at some point recently. Fluid in the brake fluid chamber is a bit manky so I might bleed the front brakes in time. 

 

Noticed someone attempted to stop a heat shield rattling with hot melt glue. Nice choice of glue on an area that gets hot 🤣

 

Air con panel arrived too, so fitted that to see if that sorted the fan issue. Reasonably easy to get to.

Stereo doesn't fit properly, looks like someone broke the screw holder that goes into the plastic. Crazy thing this plastic considering its supposed to be holding the radio in. I think someone forced this plastic piece in the wrong way around and broke it. I can't say the design of this car doesn't have the feel of durability as a priority.

Discovered that someone has fitted a Aux port for the stereo which is neat.

Also a whole load of extra wires and connectors hidden behind there. I think it might have had an ancient car phone mount at some point in it's past. The mic looks like a 2000-era Nokia hands free mic.

 

Test fitted the new panel. Fan still doesn't work properly. Damn, parts darts fail.

 

So dug into the glove box to see if I could find the hedgehog resistor pack.

Connector wiring doesn't look very promising. Screw was loose so someone has been in here before.

Single screw and connector it was out. 2014 date code suggests it's been replaced. These are NLA new and don't seem to have any aftermarket options available either.

Connectors definitely had too much heat through them.

 

So what caused that?

I think two things.

Firstly, despite being a genuine part, that terminal doesn't look like it was soldered properly. I don't think overheating has melted it as the solder hasn't flown elsewhere. 

Compounding the issue is the pollen filter is filthy and full of leaves. This will cause resistance to the airflow and make the fan work harder. (I don't know what that random yellow wire goes to yet!)

 

So what next? 

Second hand units can be had for £80 or so. More than I want to pay really. Plus I need to sort that connector. There is one with a loom snipped at the resistor which could be an option.

First thing I'll try is cleaning all the contacts up. However cleaning crimp terminals isn't easy and often doesn't really work as you can't get any mechanical cleansing tool in there. As this is a high current connection, if it's not clean then it'll just happen again.

Another option could be to drill a hole through the case and put a fly lead from that terminal directly into that dodgy melted terminal. Either soldered directly or with a bullet terminal/similar. However that said the other terminals aren't in great shape either.

So the next thing could be snipping the connector and soldering directly to the terminals. While bodge tastic, it'll work. Given that if this every needs replacing again will need a new loom connection anyway, perhaps isn't so bad thing to do? Plus lets face it, this isn't a low mileage minter. It's a scruffy high miler that is unlikely to be around for another decade. 

Or of course pay out for a second hand resistor pack and a loom connection. But that's something that could be done if the above doesn't work.  

[cort16]

Have you called BMW to see if they have it? A few times I struggled to get second hand bits for my Bavarian heaps so called BMW and they could get it for less than I thought. 

I've also been told stuff is NLA then when I've called the dealer they've been able to get it. I could even get obscure parts for the 320si. 

[SiC]

3 minutes ago, cort16 said:

Have you called BMW to see if they have it? A few times I struggled to get second hand bits for my Bavarian heaps so called BMW and they could get it for less than I thought. 

I've also been told stuff is NLA then when I've called the dealer they've been able to get it. I could even get obscure parts for the 320si. 

No I haven't but I suspect it'll be hundreds of pounds. I did see a forum post from last year that said the resistor pack was NLA and factory back ordering since 2019. 

Maybe one of those things that they only make when enough orders come in?

Either way, I don't really want to spend hundreds on this if I don't have to. Otherwise I'll be in money wise at more than buying a bigger engined nice one 🙃

Still need to buy a cheap laptop to run dodgy software and reflash that airbag module so it behaves properly on the network. 

[beko1987]

I vote for neatly extending some wires out of the casing and refitting that then a short length of slack and some neat connections back to the rest of the loom, either crimps to test then solder or find a fancy suitable plug? 

 

[Cookiesouwest]

12 minutes ago, SiC said:

No I haven't but I suspect it'll be hundreds of pounds. I did see a forum post from last year that said the resistor pack was NLA and factory back ordering since 2019. 

Maybe one of those things that they only make when enough orders come in?

Either way, I don't really want to spend hundreds on this if I don't have to. Otherwise I'll be in money wise at more than buying a bigger engined nice one 🙃

Still need to buy a cheap laptop to run dodgy software and reflash that airbag module so it behaves properly on the network. 

I'm upgrading my think pad as its slow AF.

Might be ok for your purposes though.

When my newer one arrives next week from Markeh, you can have it.

Specs are as pic

[riek]

Cotswold BMW do a discount for members of various BMW forums, m3cutters etc. you don't have to be active as a member either, I've only ever posted in the Cotswold section

 

[cort16]

1 hour ago, SiC said:

No I haven't but I suspect it'll be hundreds of pounds. I did see a forum post from last year that said the resistor pack was NLA and factory back ordering since 2019. 

Maybe one of those things that they only make when enough orders come in?

Either way, I don't really want to spend hundreds on this if I don't have to. Otherwise I'll be in money wise at more than buying a bigger engined nice one 🙃

Still need to buy a cheap laptop to run dodgy software and reflash that airbag module so it behaves properly on the network. 

I've found with BMW the small things you think will be cheap like nuts and bolts and expensive but parts you think will be expensive are fairly prices.

Real oem has it has $60 so I imagine it'll be the same in £'s from BMW in the UK. 

[SiC]

That airbag light.

Programming the module was a massive pain. The steps aren't clear on what to do to actually flash it, not helped being in German. So ended up thinking it was flashed so carried on but got coding errors.

Anyway ignored the guide and used instinct on the GUI. Ended up flashing okay. As a firmware engineer by trade, these progress bars especially make me nervous as I see them fail all the time when developing but I have other ways of fixing it when my own stuff. This stuff is bricked if it fails.

 

Once that was sorted I realised that I was missing the expert profile in NCSExpert. Found a package with that and got the coding reset to default.

But then the light didn't clear. INPA error code gave an error of unterbrechung sbe1. Not sure what that was I googled it. Which helpfully gave all results for German websites too. 😬

Plugged in my Foxwell and it gave something more intelligible.

Ah! Okay a proper error. Quick Google of seat occupancy detectors find loads of emulator modules to make the car think it's okay with aftermarket seats. 

So with a failed sensor, it possibly means replacement seats are needed. Either the box is at fault or the mat. The error is coming back as open circuit so I presume it's the mat at fault. I'd rather not buy replacement seats if I can just make it think it's all okay.

Checking the coding of the drivers side I found it was disabled. Unsurprisingly as it assumes someone is there all the time. Anyway I reckoned that it would be safe to disable the left occupancy sensor and it'll just fire the airbags as if someone is there. So coded it out with NCS Dummy and sent the code in with NCSExpert.

VAG coding with VCDS is a million times easier and simpler than this shit.

Taken all bloody night but I've managed to get the airbag system sorted and the light is now out. Success!

 

Now just need to figure a solution for the fan resistor. Pretty sure I'll just chop the connector and solder it directly on. But first connect it all up on the terminals to make sure the resistor pack is indeed good. 

[cort16]

Seat occupancy sensor is an old BMW favourite and he scourge of every e46 owner.

[SiC]

2 minutes ago, cort16 said:

Seat occupancy sensor is an old BMW favourite and he scourge of every e46 owner.

I'm a bit nervous coding it out as I don't know the full consequences. However if it knows all about the other airbags it can fire, then surely it should fire them if the seatbelt is on - like it must do on the drivers side. Got to be better than an emulator that most likely says to the car that there is no-one on the seat (otherwise the seatbelt warning would go off all the time).

[cort16]

8 minutes ago, SiC said:

I'm a bit nervous coding it out as I don't know the full consequences. However if it knows all about the other airbags it can fire, then surely it should fire them if the seatbelt is on - like it must do on the drivers side. Got to be better than an emulator that most likely says to the car that there is no-one on the seat (otherwise the seatbelt warning would go off all the time).

I don't know. On the e46 you could buy some little box with a resistor on that tricked the car into thinking the sear occupancy sensor was working.

I was never quite sure if it premaritally told the car there was someone in the seat or not.

I think I would fine with mapping it out for myself and to get it through the mot but not sure I'd want to sell it to someone who then thinks the airbag system is fully functioning. 

[SiC]

2 minutes ago, cort16 said:

I don't know. On the e46 you could buy some little box with a resistor on that tricked the car into thinking the sear occupancy sensor was working.

I was never quite sure if it premaritally told the car there was someone in the seat or not.

I think I would fine with mapping it out for myself and to get it through the mot but not sure I'd want to sell it to someone who then thinks the airbag system is fully functioning. 

Yeah that's the emulators I said about in my last post. 

Thing is, they must make the assumption there is always no one on the seat. If it did then without the seatbelt buckle in, it'd chime the seatbelt warning all the time.

I'm happier thinking the airbag system will work with the seat occupancy coded out than with an emulator to make it think no one is sat on there. 

I may have a fiddle around with the connector and see if it just needs a clean up. And check the resistance to see if it's really open circuit or just a duff connector. 

[SiC]

According to the internet basically the mat exists to not fire the airbags if no one is there. If coded out all airbags will fire. Apparently born out of people doing so and then crashing later on (BMWs crash a lot? 🤣)

Idea of the mat is to reduce the number of airbags firing and reduce insurance costs.

https://www.e46fanatics.com/threads/disabled-seatbelt-occupancy-detection-in-bmw-scanner-1-4-does-that-mean-my-air-bags-wont-go-off-or.1284514/

 

The first option - the "occupied" value resistor instead of sensor provides the standard SRS behaviour during crash as the seat is occupied with functional sensor = airbag deployment.

The second option - You must to perform both steps, if You do just one, You still get the airbag light. If You code the SBE out of SRS but You will leave the SBE box connected to the SRS, You still get the light as there is connected equipment to SRS which should not be => light on

 

I did the second option many times yet to E46like bodies generation cars and even the E6x, E9x like bodies generation cars too, so I have the SRS behaviour experience as well, because of feedback from several guys crashed their cars with this mod.

 

The SRS without SBE equipment deploys passenger airbags similar and parallel to the driver's airbag, so passenger safety is not compromised.

 

Deployed passenger airbag in old bodies (E46, E39,..) is not a big deal comparing to the damage of the rest of the crashed car, meant the repair cost of the rest of the car is much bigger than a replacement airbag unit, so You can disregard whether it is deployed during the crash or not. This mod can stay in the car and spare some money spent for occupancy sensor replacement.

 

Another situation is in the new bodies (E6x, E9x,..) as they often do not have airbag replacable dashboard cover and passenger airbag deployment damages the dashboard itself (needs to be replaced after crash = more expensive repair), so this mod is then recomended to be just a temporary solution.

[SiC]

Of course you can believe everything on the internet and random internet forums...

[JakeT]

It’s E46 based so will have a fucked occupancy mat. Kneeling on them (or a bony arse) ruins them and they go open circuit. One of my E46s had the issue and I put the box to stop it. I don’t think the seatbelt light is on for passenger, so you should be okay. On my few E46s the light isn’t on for the driver as standard. It comes on with the ignition and then goes off, buckled or not.

 

You're right though, it will fire the passenger airbags no matter what.

[Oi_Oi_Savaloy]

Pity you can't just put a bit of wire in the connector that plugs into the seat mat (which is what I've done with the ride on mower - it's in case you get off the mower and the deck is still turning and stops those sorts of accidents.............which isn't an issue with mine as the deck doesn't work (taken the belt off) and is just used to cart a small trailer around the yard/garden.  

[Oi_Oi_Savaloy]

Amazing work on the re-programming thing though - way beyond my capabilities but I definitely think you've cracked it.

[purplebargeken]

Amazing work Si, wish to fuck that I could understand a single word of what you typed though lol.

[SiC]

I think I'll probably look at getting new seats sometime if any cheap ones come up. I don't have any doubt that disabling the passenger detection mat will still make all the airbags fire (my wife or me will be sitting there after all). But the passenger side is missing it's back board which annoys the heck out of me.

I actually really like the rental car spec fabric seats in convertibles as they wick away sweat rather than sitting on the surface. However I've never seen fabric seats on any Z4 before. Must be incredibly rare.

 

As the weather is so stonking nice today, I made an effort to put the car back together. So I popped the resistor pack in to test that the fan now works properly. Then put the case on. 

The crimp contacts I cleaned the insides of with contact cleaner and a set of carb jet cleaner wire. 

It all works fine but I'm not convinced the contacts will not fail again. However it does prove the resistor pack does work before permanently soldering it in. 

 

I hoovered the pollen filter area out as much as I could. I have a new filter coming but it's not arrived yet. So hoovered the old one out and stuffed it back in as a short term measure. I don't want leaves and other crap to jam that fan up. 

Gave the interior a good hoover out and wipe down with interior cleaner.

Then took it for a spin.

Don't be fooled by the photo making it look tidy. Definitely a 10 footer car and stuff like this is noticeable closer up.

 

Anyway gave it a quick blast then probed the discs for their temperature.

Rear left (new caliper)

Rear right

 

Fronts were both 62c.

 

Hmm. That rear left is still much hotter than I'd like with quite a temperature difference. Could either be it's braking better than the other side or the flex pipe is causing a flow restriction.

I did jack each side up and they still both spin freely and about the same.

I think I need to put some more miles on it first and let the pads bed in a bit before doing much more. I do suspect the pipe might be causing a bit of restriction too and compounding the issue it had. 

Right now though as the wheel still spins when in the air with not a lot of drag, I think I'll just put some more miles on before going further. 

[timolloyd]

I had the cloth seats in my 2005 base spec 2.0 company Z4. I thought they were OK, and as you say, nicer than leather in an open car.

[Dick Longbridge]

I had the rare M sport heated leather in mine - they were immaculate, too. I ended up selling them for decent coin and sticking a bargain pair of low mile standard heated leather seats in instead, once I'd decided I wasn't going to keep the car long-term. 

I've never seen fabric seats in a Z4. 

[SiC]

Why is it some people have zero problem with some brands and others always have issues?

I have never had anything ever problematic with Hondas. Just get in and drive. VAG mostly the same - despite others always having issues with them. 

For me it's BMWs. Whether hire car or ownership, they always seem to want to try my patience.

Last night I filled up the tank with petrol in expectation of using it today. On getting back the right hand indicator started flashing rapidly. But the front/side/back were all lit?

Well it turns out these have two indicator bulbs in the front headlights. I'm sure there is a BMW indicator joke in there somewhere.

Annoyingly they use a weird bulb that very little else uses. H21W. Ended up picking one up for a fiver in Halfords. 

Fitting is through the wheel arch with a flap you can just about remove on full lock. Then a Philips to unlock the bulb holder.

Today I set off and went to the in-laws. As a way to persuade me to go, we took the Z4 and planned to go to Avebury. While taking the scenic route along the A4, I decided to push my luck and detoured at Atwell Wilson Museum instead. It happened to be drive it day today, so they had plenty of visitors. I'll do a separate post of that in a moment with photos I took.

Anyway back to the Zed which got to the in-laws fine.

The way back we went down the A34, along the A303, past larkhill and through Wiltshire/BANES back home. Along the A34 I had the Emissions light ping up. 

Also noticed that left corners gave a worbling brake noise. Pull up the handbrake would stop this for a bit. So I'm pretty sure something in the handbrake shoe/cable mechanism is sticking. Tbh the handbrake always has been a bit mushy and doesn't hold the car great. 

I hate dealing with shoe handbrakes on the driveway, so probably throw it at a garage to be sorted. Probably needs a clean up, adjustment and maybe a few parts replacing.

We got home fine and covered 187 miles. All in I've probably covered nearly 500 miles since I've owned it. Not bad considering its spent a week on axle stands. 😅 

Still, I came back to Engine light, bulb out light and dodgy brakes. BMWs seem to hate me.

In better news, it's indicating 36mpg. Which if true then is stonkingly good for a 6cyl. That's a mix of motorway, fast a-road and some b-roads.

Also the blower fan has been well behaved the whole time. So far it's just had cleaned up contacts and all put back together. I don't expect it to last as is. I plan to remove it again and hard wire it by soldering directly to the contacts on the hedgehog resistor pack. But I know that resistor pack is good and I can do it in confidence that it's very unlikely to need removing again.

 

What gave that light?

Hmm. Google suggests its often an intake pipe splitting. I pulled it out and it looked fine. 2017 date code.

What this does have is the pipe that goes to the firewall to parse on engine noise. It makes the 6cyl roar louder. While quite nice, it gets bloody painful at 5k+ rpm. This usually is only fitted to the 2.5 and 3.0. Almost certain it's been retrofitted on this. The clamp to the intake hose is Pearl which is definitely not OE BMW!

You can see the box just under the brace bar.

 

This has a diaphragm in it so it's not a direct connection between the interior and intake. Otherwise unmetered air would get in. 

This isn't completely air sealed when sucking. Some air can get in. You do really have to suck though.

I'm wondering if this might be causing the code. I am tempted to remove this as it's a bit too annoying. Probably better on the bigger engines as you'd rev through it much quicker than this.

While I was there, I removed the throttle body and gave it a clean. I've seen much worse but it was dirty enough to make it worthwhile. Bit of a PIA to remove. Not TFSI awkward but still fiddly. Took me a good 20mins to remove and similar to put back in. An annoying bracket is in the way that was a fight to get past.

After

 

I've cleared the codes for now and I'll have to see if they come back. The front lambda I can see and it doesn't look that old. I need to check the paperwork and see if a decent brand was fitted. If it comes back, I'll do some more investigation. My suspicion is a vac leak somewhere.

 

 

 

[SiC]

Mix of Atwell Wilson photos. No particular order except roughly the order they uploaded in. Maybe some repeats as I walked around and took them again.

Good mix of cars outside. As I was leaving the classic USA contingent was arriving. Presumably late from all their fill up stops on the way.

While the Z4 is not a car I'd usually put on show for somewhere like this, it was the only one and adds to the mix of cars. Better than arriving in my wife's Honda Civic Estate.