2005 BMW Z4

i don't think it was a good idea, but i found a 2005 BMW Z4 on an auction website.
it had 6 previous owners, and was repossessed from the 6th owner.
at some point, it had an accident and was deemed a total loss, so salvage title was issued.
it got rebuilt, then some point had some more front-end damage... anyway, i have it now.

Stats

Year2005
MakeBMW
ModelZ4 (E85)
Engine3.0L I6 (M54)
Transmission6-speed manual
Init. Mileage99,654
Curr. Mileage101,322

Notes & Work Done

12/31/2023

Happy New Year!

i finished the lower control arms a long time ago (of course), it was a PITA, but it got done. everything works fine, but still have some stuff left to do.
i haven't done the misc fluid flushes (brake, transmission, diff, coolant) nor have i replaced the engine mounts. probably do that when it gets warmer.

10/7/2023

did an oil change, replacing the oil i used on 11/29/2022 (5w-30) w/ the oil i bought on 11/23/2022 (liqui-moly 5w-40). sent sample to blackstone.

rear lower control arms in progress...

10/6/2023

our camping trip was postponed due to an issue with kuba's alternator, so i decided to finally get working on the z4 again.
i replaced the steering rack & tie-rods today, 2x bolts+nuts holding the rack in (15mm screw, 16mm[5/8"] nut), 2x nuts holding the tie-rods (something bigger than 15mm), and a hex-screw (E14? E11?) connecting it to the steering linkage.

it took me a few hours, was in no rush and went in blind. it steers, but severely misaligned, hah.

9/8/2023

my MEOW plates came in on Saturday (9/2), so just over a month since i mailed the paperwork.

today i replaced the serpentine belt and the a/c belt. i did not take a photo of the serpentine belt diagram prior to removing the belt, so it took me way longer to put in the new one.

to loosen the a/c belt tensioner, you need a T60 Torx socket and shove it into a torx-looking hole next to it, then turn clockwise (i think?).
to loosen the main belt tensioner, you need a 16mm hex socket, it'll be in the middle of the assembly. turn clockwise (i think?).

i slammed the car into a curb a few weeks ago, bent my tie-rod in front and lower control arm in rear.
ordered a used steering rack from eBay for $327 total, it came off of a 2005 E85 Z4 (but 2.5L), so that worked out well.

7/17/2023

sent in paperwork to get CPMF plates on this car, MEOW is available :)

picked up the car from Bella Auto Interiors & Convertible Top Repair on Friday (7/14) afternoon.
it was done pretty quickly initially (new top material & new cylinders + motor) but when i brought it back for final touch-ups, things went awry...
i told Richie i'm in no rush with the car, and he definitely took his time, but he eventually figured out which new part was faulty, and finished it all up.

the drop top is great, i've been trying to get more miles on the Z4 instead of the 428i, so it's a blast driving this thing in the summer.
however, my left mirror fell off while sitting in Richie's lot, so will need to get a new one... 1/2 of it is duct-taped at the moment. (i put on a new mirror after 7/26, it cost me $119 not incl. tax!)

4/20/2023

i kept ordering parts and working on it, and hadn't remembered to update this page. it's mostly done.

    delivered 3/11 more info to come!

11/30/2022

update: it took under two weeks to get the plates, but didn't get the title until i called the office.
they wanted some form from the repo company, once i sent that to them in the mail, i got the title shortly thereafter (lost track of time).

yesterday i mailed out title & registration forms to IL Secretary of State, as i got the title & related documentation from Michigan on 11/29. we'll see how long that takes.

i've driven 121 miles since the oil change, and haven't experienced any issues. fingers crossed.

several things arrived today:

11/29/2022

yesterday i convinced pawel to try to weld a nut onto the snapped bolt that's stuck in the oil pan. it was a SUCCESS!

i got a new oil drain plug from Patrick BMW for ~$11.
got kamil to get some oil on his way to the office, ~$55 for 10qts.

i had 3qts left in a castrol bottle from my first oil change, used that to flush out any metal shavings stuck in the oil pan.
once kamil arrived, i used another 3qts from the oil he bought to flush anything out, again.

i screwed on the oil drain plug successfully, and poured in ~7qts of oil.

i replaced the front bulbs, one of the front right turn signal bulbs seems finnicky, but oh well.

11/25/2022

my front left low-beam xenon was starting to die on my 428i, so i bought a pair along with bulbs for the z4.
i also bought new trunk lid lift supports, as my trunk can decapitate someone in its current state.

11/23/2022

not much has changed since last update. the audio cable mentioned comes in sometime after the 6th of december or so.
over the weekend, i ordered a new, proper ambient temp. sensor. put it in, it works. ~3F variance.
today one of my front turn signal bulbs went out, will just order a whole set of bulbs and replace 'em all at once.

i also ordered an oil change kit - i wanted to send a sample of the castrol oil after ~500 miles of use to blackstone. this is where things go wrong.

i drained the oil, no big deal. changed the filter with my new "36mm Engine Oil Filter Cap Socket" (perfect tool). great.
i go to screw the drain plug back in - not tightening for some reason. kuba gets under the car -- "uh you've got a situation buddy" -- i snapped the head off the bolt.
silly mistake - tightened instead of loosened when i was taking it off, which makes sense as to why it suddenly felt like it loosened up.

i decided to internally weep for the rest of the night, especially after i looked at how to take the oil pan off - terrible.

oil sample sent off to blackstone. oil change (in-progress?) done at 100,139 miles.

11/16/2022

i went with janek to pick up rosarios in the z4, and my bluetooth audio didn't work again. i'm pretty sure i damaged the DSP coaxial cable's connector before, and now it slips out.
i bought a male-to-female 1ft extension cable, and i'll hot glue / tape it up to never move again.

11/15/2022

today i got an email from northstar motorsports, saying the brake pads will be in from japan this week, so that's cool.
i went back to the amp, reconnected the DSP coaxial cable, and the GROM unit started working again. it's a really sensitive connector, as i pulled it out slightly whilst playing music, and it stopped quickly.

since my work cart was clean, the only thing i had left on it was the headlight level sensor rod. i knew where it was located, thanks to my mechanic, and figured it would be an easy fix.
it was... somewhat... of an easy fix, just a lot of shoving my arm in places under the car and in awkward positions. all i needed was a 10mm socket, swapped it out, voila. todo: add pics

today i ordered a new fuel pump and fuel filter. according to kamil, and later verified in the haynes manual, the fuel sensor is not a separate unit. basically, i have to replace the pump.
if i'm doing the pump, i'm going to do the fuel filter as well. that'll take some time, so i'll do it during winter break.
total: ~$670

11/14/2022

i don't recall doing anything to it yesterday, but parts from 11/11 came in.

first thing i did, was put the lock cover in. easy!

i stripped the temperature sensor wires under the car, and on the wires from fcp euro. i soldered facing up while on the ground, but it worked. put some shrink tube, heated it up, nice.
the temperature sensor seems to be intermittently + 20F off from actual temperature. it is resistance-based, and we couldn't find any issues.
after a few hours, it said 64F when it was 62.?F inside, so it was reading correctly at some point.
i suspect it might have something to do with it being zip-tied to the chassis, and warmth from the chassis is affecting it? the correct values were read when the car was off for a few hours.

so the ignition service kit i ordered, it contains the proper coils but the wrong spark plugs. they're for 2006+ Z4s, probably for N52 engine.
i bought proper spark plugs for slightly higher price at autozone, and returned the wrong ones to fcp euro.
replacing the coils and spark plugs was pretty easy and painless. kuba showed me how to use the torque wrench (22Nm for M54 engine).
i ended up using the [insert model# here] spark plugs.

afterwards, i replaced the cabin air filter. that was probably the toughest thing so far...
i watched this video and was able to get it out eventually.

the last thing i did, was test out the 'new' amp, it also came in today!
i connected it up, and FM/AM/AUX worked just fine, so i guess the pin i broke off really matters. however, my GROM unit did not work... i decided to finish for the night and check it out tomorrow.

11/11/2022

forgot to mention, my glove compartment door hinges cracked off (plastic). i will design new ones and 3D print them later this week.

didn't do anything to it today, just drove to 06C and back.
yesterday/today's fcpeuro purchases: total: ~$325

11/10/2022 - evening

what a terrible day :)

lightbulbs work, all rear ones replaced. yay, no more 'bulb broken' light on the instrument cluster.

i ordered ambient temperature sensors without the connector & wires. patrick bmw has a 'repair kit' for ~$26, which was completely useless, minus the connector that i needed.
bmw used to stock the actual pre-made cables, but don't anymore. i ordered some on fcpeuro for ~$4/ea.

i also ordered the headlight automatic level sensor arm, since mine is clearly broken.

i managed to break a pin on my DSP amplifier and now i have no audio, even with the GROM unit fully disconnected and everything back to stock.
i bought a used amp on ebay for ~$280, hopefully that solves my issue.

i learned how to solder (thanks janek), and made longer cables for the DSP conversion adapter. wired them up into (+) amp harness, pin 4? .637V when ign off, ~12V when ign on. (-) to a bolt on frame.
the unit works, my phone connects as soon as i unlock the car, so that's cool. just no audio now... gotta wait n see if the new amp fixes my issue.

11/10/2022 - 1 AM

yesterday was a very successful day. the GROM BT audio unit came in, and i managed to spend several hours looking for two stupid cables (separate page to be made later).
once i found those cables, i temporarily connected the unit directly to the battery, and started the car. instantly, my phone was able to connect to the unit.
i played some songs, answered a phone call (haven't connected the mic yet though), and played with the steering wheel controls.
it does not support cyrillic text on the radio display, but oh well.

the lightbulbs are coming today, and so are my ambient temperature sensors. more on that later tonight.

the northstar motorsports people called me, something about the compound is no longer available and has been superseded. would i like the superseded ones?
i said ok whatever. they're getting the superseded ones shipped from japan. cool.

11/09/2022

yesterday the car misfired, which may be an actual issue, as the ecu had misfire codes before i cleared them for a fresh state.
the coils look to be factory, so might as well just replace the coils & spark plugs. fcp euro has an oem/bosch service kit for ~$215.

11/08/2022

today i learned that the z4 does not like LED bulbs. tried replacing the rear tail light with an LED bulb, it would not power on.
i verified the bulb works by connecting two wires to a 12V car battery and it powered on, as well as with the bulb in the
socket and connecting the socket. incandescent it is. i bought a 10-pack on amazon for ~$13, and 2x orange bulbs for ~$9.

11/07/2022

yesterday i dropped off the z4 at my mechanic's shop. this morning they looked it over and gave me a lengthy list, albeit some of it seems doable for me.
i think the general consensus at the office is to leave the suspension work to the pros.

the car had a muffler delete, which explains why it sounds so good.
LukeG Workshop
i ordered new brake rotors and pads.
Northstar Motorsports
UroTuning

11/05/2022

sadly i didn't take any before/after pics of the oil change & filter replacements, need to remember to do so from now on.