project SiC's consolidated moderns - 2004 BMW Z4 2.2, 2005 BMW 330i and (borrowed) 2007 Porsche Cayman

[SiC]

Might order a Vanos rebuild kit and do that too while I'm there. 🫠

Also might investigate removing the clutch delay release valve as I think it's still on here. Pisses me off when changing gear and you know it's not fully engaged after releasing the pedal. Need to suss out the clutch slave bleed nipple first and determine if that risks snapping off though.

[Split_Pin]

@Supernaut might be able to advise on that clutch delay doofleshanker.

[purplebargeken]

Clutch delay release what the fuck is that?

[JakeT]

It slows the release of the clutch by adding a restriction in the clutch line. It’s supposed to stop damage to the DMF in case the driver sidesteps the clutch. In reality that, and the awful throttle lag make for a very jerky, frustrating time driving in traffic.

[cort16]

Would it not be worth cleaning the solenoids first if you can get them out with dismantling the engine? It's not totally uncommon for the them to have issues causing similiar running and power delivery issues. Probably more so than the vanos unit itself going faulty on these cars.  it's also free.

The problem with your car having a high mileage is if you do tackle the vanos rebuild you probably also want to put new solenoids in it so you know the system is good else it good get very frustrating. 

[SiC]

5 hours ago, cort16 said:

Would it not be worth cleaning the solenoids first if you can get them out with dismantling the engine? It's not totally uncommon for the them to have issues causing similiar running and power delivery issues. Probably more so than the vanos unit itself going faulty on these cars.  it's also free.

It's something I have considered it but the exhaust solenoid is buried.

 

Intake doesn't look too bad.

 

The thermostat really doesn't look like a fun job though. There isn't much room between the front and the engine.

[SiC]

This is the Vanos adaptations at idle. No idea if they're good or bad.

They would have been reset yesterday when I reset the fuel trims (I reset all adaptations)

Presumably as they are hitting the set point and it's measuring it correctly (from the cam sensor I guess), perhaps they are working just fine?

[wuvvum]

I might treat myself to one of those code readers.  At the moment I only have either the all-singing-all-dancing Delphi-on-a-laptop setup or an extremely basic first gen code reader which literally just shows the fault code numbers and nothing else - for the sake of less than 20 quid I might as well have something in between...

[SiC]

The Creator C420 does both BMW specific and OBD2 generic pretty well. They're like £35 on eBay. 

That cheapy £13 tool is okay but a bit clunky. Kinda an impulse buy on Amazon as it was the cheapest I could find that did code scan/erase and live data. Few about with similar functionality. 

Tbh I'd probably spend a bit more and get a cheapy Topdon as the UI is probably a bit more polished. 

[SiC]

 

33 minutes ago, wuvvum said:

I might treat myself to one of those code readers. 

I should also add that this screenshot is from INPA. I believe it's the factory diagnostic tool. Literal one for the factory. Hence why it's all in German.

I have a cheapy OBD USB DCAN cable off Amazon that I use with it. It's the tool I used to reflash the Airbag module VIN in the Z4 and also reset the coding on the second hand iDrive unit in the 330i.

[SiC]

My fears about the access at the front of the Z4 to remove the VANOS is well founded.


Apparently the E85 is a different front structure to the E46 that it shares a lot of parts with.
Looking on forums where others have done it, it appears you need to use a special service tool.


I think mine will be staying put for now. Starts fine, revs fine and goes fine. No codes and it's not a startling difference when you rev it hard. Yes if feels a bit slow but that also could be because I'm going from a 250+bhp 3.0l to a 170bhp 2.2l. (When I went out in the Spitfire, with it's supposed factory 75bhp, it felt broken as I was revving the hell out of it - until I engaged my brain.) At 178k, it could well be better to let sleeping dogs lie.

I'll still do the thermostat though as that should help MPG and it probably could do with a coolant change anyway.

[SiC]

These are starting to get really cheap!

https://www.facebook.com/marketplace/item/495909132961215/

 

Cheapest by far and probably pretty ropey but I thought they'd be at the bottom of the depreciation curve already.

 

[SiC]

Checked the fuel trims again earlier. Long term is now at zero which was entirely unexpected given they weren't the other day. I mean it's good as it should indicate there is no air leak.

Short term trims are high still but I reckon that is due to the thermostat not allowing the engine to fully heat up. I need to check my E320 thread and what that did, but I have recollection those trims were high until I replaced the 'stat.

Pulled apart the CCV valve. That diaphragm is absolutely perfect. Remember this is a 2004 date coded part and very likely original to the car at 178k miles on it. 

Maybe the spring goes weaker? That said, I'd expect it to pull less of a vacuum in that scenario. 

Honestly I think this was absolutely fine and I didn't need to change it. Oh well.

High long fuel trims I suspect is a combination of duff thermostat and that leaking bung on the back of the intake. 

Thought I'd check the oil as it's been a long time since I have done. Actually I think it might have been the day after I bought it. (But I might not have done then either...)

Err, that's a bit low...

Took a good 1.6 litres to fill to the top. Oops.

Not sure what mileage that is but I think might be a few thousand (at most). I'll just have to keep an eye on it. Maybe the CCV was a bit dicky after all?

Let's not forget at 178k the valve stems, piston rings, etc all have a few miles on them and it's not unknown for a BMW to like a drink. Plus it's probably leaking out of the oil filter housing gasket, valve cover or something like that. 

[SiC]

Took the Zed for a day trip down to my parents in Sidmouth and the onto Lyme Regis for a meal along the beach (a new Greek Takeaway place that was really good) today. 

I don't do selfies very well. My brain said I was smiling but apparently my face doesn't respond to that request as I would expect it to.

 

Anyway on the way back it broke.

Cruising along it pinged on again. Daaaayum.

Codes were exactly as before.

Third code is for the thermostat heater and doesn't trigger the EML.

Freeze frame data showed sky high fuel trims. I think I was putting my foot down at the time to overtake a horse box on a dual carriageway way before it went to a single.

 

When I read the above, I was at Bridgwater services. Cleared the light and checked the live trims.

Still high, albeit lowering down..

Back home (about 30mins further) the EML stayed off but there was a pending bank 1 lean code still.

Fuel trims still pretty high.

 

God damn piece of shit. I thought I'd fixed this with the intake leak fixes. Even with non zero trims after the repairs, I'd thought they'd stay low enough to at least keep the light off. 

I'm really not sure what's causing this. Given it's both banks, it suggests intake related. However I can't find a leak. CCV replaced and while could be bad, I think unlikely given the original looked okay too.

I don't think it'd be the VANOS? Pretty sure that is causing some power loss. But I don't think it'd affect fuel trims.

Could the thermostat not allowing the engine get to temperature really cause such high trims? I find it unlikely as it's only ~7c lower than it should be. But a replacement is coming this week anyway and I'll chuck it on.

Could it be the MAF? Possibly but it seems to be reading sensible amounts when doing a live view. Admittedly graphing it against throttle and rpm should give a better indication. Just I don't have a scantool good enough to do that properly. A genuine OEM VDO MAF is like £250 new, so not something cheap enough to parts dart. The one on there looks really clean inside.

Thermostat next as that is definitely not 100% anyway. But when that doesn't fix it, I'm not sure what to look at next. Perhaps just something that might have to be lived with. 

Could also be the fuel pump/pressure regulator. However apart from a fuel rail pressure test at idle, it's not an easy one to test. Testing at idle isn't likely going to be very useful either as least amount of load/fuel burn rate.

[Split_Pin]

I'd get yourself a Creator and look at what the O2 sensor is doing. I'm away to see if I took any pictures of the live readout from my C110 when that god awful Bini was throwing it's EML.

[SiC]

1 hour ago, Split_Pin said:

I'd get yourself a Creator and look at what the O2 sensor is doing. I'm away to see if I took any pictures of the live readout from my C110 when that god awful Bini was throwing it's EML.

These have two separate fuel injection banks (unlike the Bini 4cyl with one bank) with 3 cylinders in each. Each bank has its own pair of O2 sensors. 

Both banks are reading similar fuel trims and thus both banks are triggering the lean fuel code. The front bank gives a slightly higher fuel trim reading and triggers slightly before the rear bank. Also the front bank looks to have a newish O2 sensor given how clean it looks versus the rear. I suspect the front may have slightly more worn injectors from just natural wear which would be normal. A percentage or two which is why fuel trims exist as they take into account wear.

Given this, I strongly suspect it's not a O2 sensor that is causing this issue. So more likely something that affects fueling on both banks. Usually an air/vac leak would cause this especially on an M54 - but I'm pretty certain the recent work should have nailed all that.

Only two things I can think of is fuel pump/regulator failing or MAF.

Fuel pump/regulator I'd expect power loss at high revs, which I'm kinda getting but that could be VANOS wear too. Certainly not getting a big drop out of power though under high revs which would suggest it's probably okay but I can't dismiss it as a fault.

MAF is more difficult as I'd need to really datalog to tell. Or part swap with known good - but at £200 for a new, it's a big expense gamble. Used is an unknown quantity especially given as these vehicles age and the MAFs on them do fail. Basically I really want to either diagnose it as the MAF or have literally everything else nailed before leaving only the MAF as the possibility. 

My Creator C420 usually lives in the 330i as that has more stuff that can break/stop talking and leading to the car not being able to move. 😅

That gives the same values in BMW mode as this cheapy does in generic OBD mode. Also a lot quicker on this cheapy scanner to plug in to read the values (larger font too!), so it tends to be the one I use on this more. 

[Split_Pin]

Any links to the cheapy scanner? I gave away my BMW one a couple of years ago.

Oh, and I just scoured my old Bini thread and what a horrible car that was. No end of serious running issues during 2019 and Covid 😞 Need a lie down after the flashbacks...

[EyesWeldedShut]

5 minutes ago, Split_Pin said:

old Bini

TADTS?
 

[cort16]

How does it drive when you disconnect the MAF? It'll be horrible but does it display the same issues?

 

[SiC]

16 minutes ago, Split_Pin said:

Any links to the cheapy scanner? I gave away my BMW one a couple of years ago.

Oh, and I just scoured my old Bini thread and what a horrible car that was. No end of serious running issues during 2019 and Covid 😞 Need a lie down after the flashbacks...

The Creator C420 replaced the C110i and has slightly more features. Also cheaper!

Mine was £32.50 after an eBay discount code. Weirdly there doesn't seem to be many available for sale on eBay at the moment.

There looks to be a Creator C410. Not sure of the differences.

I sold my C110 to a mate after I sold my Bini R53 but should have kept it really. They still do generic OBD2, so useful on other cars like a cheapy OBD2 scanner. 

[SiC]

8 minutes ago, cort16 said:

How does it drive when you disconnect the MAF? It'll be horrible but does it display the same issues?

 

I need to redo it since doing the last lot of work. Last time though it definitely felt more sprightly. However there was vac leaks at the time so can't fully say the MAF was an issue just that it could have been getting bogus data from a vac leak. 

I'll redo it this week and also see what the fuel trims are doing. 

[SiC]

MAF disconnected and car warmed up. I reset the fuel trims before doing this to set everything at a baseline. Below is from a short drive back from the gym when it was fully warmed up.

Idle has a habit of moving around when the MAF is disconnected. Presumably a normal trait?

I did wonder if I should have cleaned out the Idle Control Valve when I had it off. Can't remember exactly but I don't think it rattled like it should when I had it off. Didn't pay too much attention as the idle (with the MAF connected) is pretty much on point all the time.

Negative fuel trims means less fuel injected than the base map from Lambda correction. Default map is probably over fueling to be on the safe side and lambda readings knocking back is probably okay? Not sure what would be considered normal fuel trims with the MAF disconnected.

 

INPA shows a Manifold Air Pressure reading (it hadn't warmed up at this point). Where is it getting this from? I didn't think the M54 had a MAP sensor?

[SiC]

This suggests the reading I'm getting at idle are normal for a MAF disconnected. Which possibly suggests that maybe my MAF is failing?

https://www.e46fanatics.com/threads/the-infamous-unplug-the-maf-test.1298186/

(Great! They're bloody expensive new 🙃)

That said, one of the responses give 3.0g/s for his M54B22. From memory mine is around 3.1g/s, so nearly bang on. 

[SiC]

Quick look on Real OEM on the MAF part number gives this:

https://www.realoem.com/bmw/enUS/partxref?q=13627513957

Which is replaced with this in 2006:

https://www.realoem.com/bmw/enUS/partxref?q=13627566984

Which suggests it's probably an original MAF.

[SiC]

Removed the ICV (Intake Control Valve).

Pretty dirty inside and didn't move freely.

Cleaned it out, freed it up so it rattled and reinstalled.

While putting it all back together I noticed that the top part of the grille is broken on the MAF. Is this a problem? I'm not sure however I do know these grilles are specifically designed to direct airflow. While it's only a small piece, it might have an impact on it?

Looking through my old photos I noticed that it was like it before. So probably some hamfisted individual removed it a while back.

Did a smoke test again. Found that the pipe under the CCV is leaking. The very one I wasn't happy was pushed in enough. I used a long screwdriver and gave it a good shove which stopped the smoke leaking out. Down here to the right of the oil filter housing. Tbh it's unlikely you'll see it!

Despite making sure everything was in place correctly after putting the ICV back, there is a very slight smoke leak from that area. Balls. Couldn't be arsed to pull it apart again just yet as it is a tiny, tiny leak. Must be small enough that a total percentage of airflow must be minimal. Fix one thing and break another 🫠

Took it for a drive with the MAF connected.

After pulling in the trims were quite high. Then settled down after a time.

 

However what I did notice is that the MAF value fluctuated a fair bit at idle. From 3.1g/s to 3.8g/s and even briefly hit 3.9g/s. Idle is rock solid steady at 700rpm +/- 5rpm.

I can't imagine this is a good thing and it should be doing it? Would explain the fuel trims moving around too if it thinks the airflow is changing.

Apart from that CCV hose causing a vacuum leak (probably what caused the light to come back on again), I am starting to suspect the MAF might be on its way out. 

[SiC]

Thermostat arrived yesterday. Mahle/Behr unit and it looked decent enough quality.

I drove it into work and back yesterday with the thermostat heater disconnected. This should force it to be at the rated temperature of 97c rather than the ECU opening earlier using that heater. Reading after getting home was 93c. So definitely lower than it should be. Not a huge amount admittedly but enough that in the autumn/winter this will drop further.

Given I'm in here so much nowadays, I probably should replace the bonnet struts as they keep falling down. My little molegrips are handy to stop this happening while working on it. 

Slam panel removed which gave me slightly more access.

This brace is right in the way. At least I can get in through it though. Bottom hose just visible.

Drained the coolant out of the coolant tank. Didn't do the radiator as that didn't want to come loose easily and I didn't want to ruin the rad. Not sure if there is supposed to be an undertray on here?

Thermostat was four bolts. Then a clean up of the mounting face.

Filled up and drained to give a bit of a flush while checking for leaks. Noticed the coolant was pink long life. Usually on this age I believe BMW use blue coolant (which I bought some more of), so looks like someone has changed it at some point. I'll refill with long life to prevent mixing and potential clogging. Reality is that this probably be the last flush in its remaining life.

The old thermostat was date coded 2004 with evidence of internal wax element failure and leaking from the housing. So I don't regret doing this. It will have got worse and made the fuel economy go down.

 

This is where I should have called it quits. I.e. at this point I should have just refilled and bought up to temperature. Nope I went further.

The coolant tank should have a little float that tells you when you've topped up enough. This one had the stock come away from the float. I tried extracting the stick so I could reattach to the float but ended up loosing it further into the tank. I also wrongly assumed that was part of the low coolant system for the dash warning. It's not, that's a separate float at the bottom of the tank. 

Anyhow I stupidly decided to remove the tank. The final motive was to inspect it for leaks. Given the fluid had dropped already, I didn't want things getting up to a high temperature and the pressure blowing it out. 

Except it's BMW plastics and weird engineering. The tank sits on a plastic mount. For some reason this mount is essentially a quick release hose coupling that is blanked off and goes nowhere. In the process of trying to remove the tank, I broke the stupid coupling plastic where the clip pushes against while trying to prise it out. 

The tank was out at least though. It did live between the radiator and brace next to the engine.

This is the tank with the float rod thing fallen out. I couldn't even reattach it with it out anyway.

Tank is date coded 2011 so has been replaced before. No splits either and in good condition generally. 

This is the stupid clip that I broke. Literally plugs into a blanking plate that goes nowhere. Stupid design.

So I need a new tank. 

I've ordered a Febi unit with a new cap off Amazon that should be arriving later today. Thank goodness for Amazon and it's plentiful listing of Febi parts. Not cheap at £55 for both and more money spent, but I didn't want to go a generic no named brand unit and have it fail at the worse possible moment. Plus it was my own fault doing this one and I should have left it. (Even though I didn't have confidence it wasn't potentially split).

I hate dealing with cooling systems.

 

[IronStar]

I call BMW bingo!

CCV? Check

ICV? Check

Vanos rebuild kit mentioned? Check

Dodgy MAF? Check

Leaking $random hose requiring dismantling half the engine to replace? Check

Broken plastic clips that are designed in the stupidest possible way and require part replacement? Check

And for final bingo entry - thermostat housing with evidence of leaks? Check

 

I really hope that's it, and once you get all the common pain points it treats you right!

[Split_Pin]

Mine had blue in it when I opened it up so I put a fresh 5 litres of that back in when I did the thermostat.

My coolant tank is a different design and the original had split in a couple of places. I ended up bridging the plug for the level sensor to make the annoying bong stop as the level sensor wasn't picking up a signal from it. I check it weekly anyway and there's now no leaks anyway.

[JakeT]

Like IronStar says, you’ve checked them all off!

 

E46 based cooling systems suck too. That tank at 13 years old would have probably burst and left you stranded at the slightest hint of overheat, or the new thermostat actually holding temperature.

 

Still though, they sound good when they’re working. That’s worth it… Right?

[wuvvum]

I thought I'd spent too much time and money fettling my slightly knackered Z4, but you've blown my efforts out of the water!