project 2007 BMW 525d High Mileage Hero

[loserone]

Bonnet catch broken?

[SiC]

17 minutes ago, loserone said:

Bonnet catch broken?

Not quite. Washers were feeble so I popped it open about an hour in to top them up. Except the machine payment card reader was broken. So I thought I shut it...

Then must have spent another 2½hrs with it like that...! Or it came open in the car wash near the end.

[loserone]

Could have ended worse

[SiC]

Right, I've just been fed and watered.

Firstly big thanks to @robt100 for being a gent and picking me up.

 

Sooooo why did I buy a third BMW?

Well I don't like BMWs supposedly. I guess this now makes me a fanboi...

The man maths justification is quite simple for this. I bought Mrs SiC her shiny Octavia as an upgrade for her Civic and usefully big for tip runs. Problem is that it's shiny and we don't want to get it ruined by crap put in it. A good way of getting around that is having a trailer. Except the towing capacity on the Octavia is a bit crap at 1600kg (because it's a VRS with hard suspension) and the towbar kit is quite expensive. Plus we didn't really want to hack the bumper apart to have it fitted.

Naturally the solution is to buy another car!

I did consider something like a cheap Zafira/Scenic/etc but they're not exactly thrilling to drive and would be good to have something I'd like to drive. They're not that cheap either.

Hence another BMW. One basically at a similar price to the above MPVs. Made sense to me.

 

Also having a diesel that does 40+ mpg on a run is much more preferable to my wallet than the 22-31mpg the 330i gets. As I'm doing a lot of driving back & forth to the flying club for lessons, current fuel prices make it quite expensive.

I'm also considering going down the Microlight Flexwing route (basically what most think what is a Microlight) in the future and they're easily storable at home by towing them. I haven't told Mrs SiC that I might be getting one of them sometime yet though 😂

 

The drive back was mostly uneventful. Some spectacular thunderstorms around Leicester bought some extremely heavy and intense flooding. The old girl handled it like a champ.

It drives really well, especially as it now has 257k on the clock. No knocks/bangs from the suspension and it's remarkably compliant. Much more than all my other cars. 

Performance wise it doesn't feel that quick? Not sure if it's just the miles on it, moving a big car with not a huge amount of power or that it's the lowest power to weight ratio of all my moderns. Or there is something wrong. Under 2.5k it feels especially flat - an rev range that modern diesels usually pick up well and give a turbo powered torque kick. This doesn't have that. Or I can't feel it from just being used to more powerful cars.

The interior is super clean and fresh. Really quite nice place to be sat and has held up so well. You would really struggle to realise it's done quarter of a million miles.

Being an old BMW there is a laundry list of problems. Mostly all minor and niggles but stuff I'll sort in due course nonetheless.

Biggest and most annoying issue is the interior blower fan has stopped working. I need to look into it more as I know @robt100 replaced it recently. Maybe the original BMW controller has failed? Or could be a connector issue - I know FEBI stock repair kits.

Also on that same note, the heater is not really blowing much heat. It could be that the ram air from outside isn't enough to properly allow it to heat. But I think it's more likely the thermostat(s). A quick check with my OBD scanner says it's only 70c after that long run. Far too cold and won't be helping the DPF regen properly at that temperature - there is a DPF code stored. There are two thermostats - main one and one on an EGR cooler. Common issue and hopefully not that expensive for a good quality unit.

 

All the other issues are more niggles:

- Washer jets are feeble. My E90 did this and was the washer filter screen gunked up. Annoyingly it is easily done if washer fluid is mixed. Back in the day, BMW wouldn't warranty this job if you didn't use their expensive genuine washer fluid... Should be an easy job if the tank isn't hard to get to.

- Remote Central Locking is not working. These aren't really well set up for the key and it's annoying. I believe @motorpunk had it coded out by a specialist after one of the keys went missing. Hopefully the chances of that key being used to steal it now is quite low. I should be able to disable that key too. Anyway I want the remote central locking back!

- Parking sensors don't work and throw an error. Code reader says front left and front centre have wiring or sensor issues. I might do a dirty and just disabled the front sensors entirely by coding them out. Not least because I'd rather have the rears working at least and you can see the front easily enough. Plus...

- ...Front bumper has bad acne and I wouldn't feel bad if I caught it during parking. I might enquire how much it would be to be repainted. Even if the colour match isn't great, it should be better than it is.

- Car battery is throwing warnings that it's flat. Probably could do with a new one. No doubt an expensive AGM unit. It'll mean that every BMW I've bought has needed one!

- Towbar doesn't fold back in. I didn't realise this was a factory fitted towbar complete with a button to retract it. No doubt I'll do my shin in on it at some point and wish the retract mechanism worked.

Finally the front wiper arc really pisses me off. BMW are god damn lazy. They did it properly on my Z4s and 3 series. Why not the more expensive 5 series?

 

I got a solid 43.5mpg on the way back. Not too bad and I imagine will be possible to improve with those thermostats replaced.

 

So all in all I'm very happy with it. Should do the job it needs to admirably. A few things to de-snag but nothing surprising or awful.

[robt100]

Power delivery wise, it does feel very petrol like in the fact it is much punchier up-top. Not sure if thats down to the de-tuned nature of the 525d engine as the lesser of the 3 litres, a remap might give it the low down grunt back, or getting the service done might release a few ponies. I'm guessing percussive adjustment didn't get the fan working again. wonder if it is the battery low,  AFAIK its a "normal" 019 battery in this one, then again, that might be why its low! 
DPF code might be historic from back when @motorpunk had it cleaned out, think there is paperwork for it in the folder somwhere 👍

[motorpunk]

Great to see this find a new home. The bonnet catch was occasionally sticky. Needs a push, that’s all. Had a new battery in my ownership. I recall the garage asking me if fitted the right one as they didn’t like it, I think I had KwikFit or someone fit it, the receipt is in there. Sluggish? I didn’t find it so but I drive like a granny. My 640d doesn’t feel that much pokier and has 100bhp more. Factory towbar is stuck in out position, I think it’s a mechanical failure inside, I never used it, I think there’s a flashing light near the fusebox for that. Parking sensor is almost certainly a broken wire. Paint is due to mileage. Dent is down to my shit driving. Will update on more when I get a tick. PLEASE look after Ron (it’s the only car I ever named) .. Ron Burgundy. 👍🏻
 

ETA - Sluggish at slow speeds. Is the clutch slipping? The clutch is absolutely ancient.

[SiC]

These are the codes for the front parking system

Might be wiring but ime it's usually the sensors (they're cheap anyway). Coding out the front is a free way of getting the rears working again until I get around pulling the front bumper. If I'm pulling the front bumper, I'd like to get it painted too.

I'll give the bonnet catch a look and cleanup when I've done the thermostats. 

Just ordered a pair of Febi thermostats. Would prefer Gates or such but Amazon can get them to me quickly.

I'll take out and give the battery a good charge first. Might simply just be age - iirc you had it a while and if the battery was fitted early on, then it's probably still 6+ years old. I noticed in the paperwork that it's got a tracker fitted and if that's still wired in, they can munch through parasitic power quite heavily. At least the one on my Boxster did till I ripped it out. If I find it, I'll remove it as most aren't usable anymore as they need the now dead Pager network to activate them.

10 hours ago, robt100 said:

I'm guessing percussive adjustment didn't get the fan working again.

I did try that and enough to bruise my hand 😅

I was in it late last night with the code reader again and I could hear a clicking/tapping every few seconds. Then after a few minutes it stopped. I'm wondering if something is catching it and it keeps trying to turn on, jams and then stops. After a few minutes trying the control unit gives up and shuts the lot down. When I get a moment, I'll pull the lot out again and see what's going on. Never know, might just been a leaf got stuck down there with the new motor and jamming things. 

[motorpunk]

On a very, very long drive on a French motorway, years ago, with cruise on and climate on, I noticed that the fan would blow slightly harder for a few seconds once every two hours or so. It’s funny how in tune one becomes when doing so many miles in a car.

That said - I had no idea it has a tracker!

[motorpunk]

Pic from Lincolnshire a while ago. 

[MrBig]

18 hours ago, Hawkeyethenoo said:

It was actually a man in leggings. Hope that helps. 

This did not get enough credit 😁😁

[Bren]

I think these are about 175 bhp - the 530 is 218 ( I think) so it's never going to win any traffic light GP's.

 

[SiC]

4 hours ago, MrBig said:

This did not get enough credit 😁😁

I didn't understand it!

 

1 hour ago, Bren said:

I think these are about 175 bhp - the 530 is 218 ( I think) so it's never going to win any traffic light GP's.

 

194bhp I think on these facelift M57TU2 3 litre 525d lumps. Still not a huge amount for a weighty vehicle and the least power out of all my moderns while being one of the heaviest which maybe where it doesn't feel as spritly as I expected. Mostly feels a bit flat low down and doesn't have the big low down torque surge that I expect from a modern common rail diesel that you get even on less powerful vehicles. Once above 2.5k or so it's not too bad though. Maybe just the VNT is a bit seized up. 

[dome]

Did the 525d get the intake flaps of doom that M57s are known for? If they're not functioning/have been deleted then that might affect low down torque.

My 530d had been remapped to stage 1 which is around 270 bhp. 

From memory the 525d has smaller injectors and possibly something else which limits what you'll get from a remap, just in case you were thinking of doing that. 

[SiC]

20 minutes ago, dome said:

Did the 525d get the intake flaps of doom that M57s are known for? If they're not functioning/have been deleted then that might affect low down torque.

It's something I was going to have a look at. The internet isn't exactly clear which M57 had the swirl flaps and not. Seemed to depend on year, power output and gearbox type over the decade and half they were fitted. 

Everyone says they don't make much difference having them removed. I know on my Saab 1.9TID 150 you could really feel when they were a jammed open/shut mix when the control rod falls off them. So if they're there, given the mileage and might be original, they could well be some broken open/shut/partially open.

23 minutes ago, dome said:

From memory the 525d has smaller injectors and possibly something else which limits what you'll get from a remap, just in case you were thinking of doing that. 

Internet definitely says smaller injectors on this LCI 3.0 525d versus the LCI 530d. I believe the same turbo though. Apparently pre-LCI 530d injectors get over this issue and you can get much more power.

However given the car has done at least 180k and possibly 257k miles on the same clutch+DMF with the same turbo/intercooler/injectors/HPFP, pushing it harder with a remap could well be a very bad idea to a whole load more trouble.

Could also be the MAF as thats almost certainly original. But usually it's high up you loose performance not low down.

Tbh I'm not going to go hunting too hard as it isn't a complete slouch. Just low down is lacking and if there is something obvious to fix, I'll sort it. 

Main priority is economy and reliability over performance anyway. Which is a major reason why the thermostats are top of the list to sort immediately. I believe it's still got it's DPF and I rather not have regen stress. At the moment I think it's only able to passively regen at long higher speeds. 75C is minimum coolant temp for it to do a regen and I'm only seeing 70C max. 

[Bren]

1 hour ago, SiC said:

I didn't understand it!

 

194bhp I think on these facelift M57TU2 3 litre 525d lumps. Still not a huge amount for a weighty vehicle and the least power out of all my moderns while being one of the heaviest which maybe where it doesn't feel as spritly as I expected. Mostly feels a bit flat low down and doesn't have the big low down torque surge that I expect from a modern common rail diesel that you get even on less powerful vehicles. Once above 2.5k or so it's not too bad though. Maybe just the VNT is a bit seized up. 

If it's any consolation I drove my friends e90 with the higher output 3.0 and it was no ball of fire.

The N57 I have in my F11 has it's critics but I cannot fault it - plenty of low down torque ( you don't even need kickdown) and reasonable fuel economy - low thirties around town and motorway figures in high forties and low fifties.

Are you going to spend on the bodywork?

[Hawkeyethenoo]

8 hours ago, motorpunk said:

Pic from Lincolnshire a while ago. 

Class shot that - the beemer could have been slightly closer, or is that just me. Nature is clearly healing and adapting which is what it does, always. 

[SiC]

5 hours ago, Bren said:

Are you going to spend on the bodywork?

If anything it'd mostly be the front bumper. It's by far the worst bit and let's the car down by far the most. 

[vaughant]

Pleased you've bought this as I know you'll do it justice.

Looked a good car and I kept coming back to it quite a lot but all those little issues, especially the ones you've highlighted since the drive home would start to piss me off if I'm honest as I knew I wouldn't give it the justice it deserves with limited time.

Silly as it's a car with moon miles on it so you have to expect problems especially for what's was eventually being asked for it.

I've been in one of these before and it went really well low down so certainly something amiss. 

 

[Noel Tidybeard]

On 15/04/2026 at 21:08, SiC said:

The man maths justification is quite simple for this. I bought Mrs SiC her shiny Octavia as an upgrade for her Civic and usefully big for tip runs. Problem is that it's shiny and we don't want to get it ruined by crap put in it. A good way of getting around that is having a trailer. Except the towing capacity on the Octavia is a bit crap at 1600kg (because it's a VRS with hard suspension) and the towbar kit is quite expensive. Plus we didn't really want to hack the bumper apart to have it fitted.

 

 

 

 

i don't fuxing think so- how is she going to cope with the drop in reliability?

[SiC]

6 hours ago, Noel Tidybeard said:

i don't fuxing think so- how is she going to cope with the drop in reliability?

Quite easily with the extra 90bhp and much more vroom!

EA888.3 with a manual transmission is about as reliable as modern cars go though tbf. Octavia is basically a generation older Golf and has most of thats previous issues ironed out.

[SiC]

22 hours ago, dome said:

Did the 525d get the intake flaps of doom that M57s are known for? If they're not functioning/have been deleted then that might affect low down torque.

I can't see any swirl flaps

Part number on the manifold corresponds to this on RealOEM:

 

Which looks like it means this car never had swirl flaps out of the factory.

Also did wonder if the EGR system/valve might be a bit clogged up. No idea if these have EGR issues but I imagine it's never been cleaned.

The EGR cooler will need to be removed to get to the thermostat. I'm not looking forward to trying to remove any of the bolts around that area. I worry it might turn into a snapped bolt fest city. 😬

[SiC]

13 hours ago, vaughant said:

Looked a good car and I kept coming back to it quite a lot but all those little issues

Tbh I think it's just @robt100 is meticulous on describing his cars for sale. There is no real massive show stoppers at all to driving this down to South of France. Maybe the thermostat might stop a regen but tbh it'll probably fine if doing long runs as it can passively regen. Fan is annoying but I've fixed it now (I still need to write it up) and it isn't as bad as many on the internet says (apart from usual cut up hand - which anyone knows is a given when working on interior trims 🙃).

It also reminded me that the biggest issue I was concerned about when buying it was the vibration at 70mph. These sort of problems can be a whole host of wack-a-mole. Driveshafts, flex discs, wheel bearings, alloys, tyres ... I could go on. 

Anyway I forgot about it having that issue when driving back most of the way back at 70mph (!)

I certainly didn't feel any untoward vibration both at 70mph cruise and sometimes a bit higher/lower when following traffic on a-roads/heavy motorway. Maybe it was just a slightly flat spotted tyre that's now rounded out with a long journey? I think a pair of tyres are pretty new by the looks of them, so maybe that helped as well. 

Or my butt sensors aren't as sensitive as Robs!

[dome]

56 minutes ago, SiC said:

I can't see any swirl flaps

Part number on the manifold corresponds to this on RealOEM:

 

Which looks like it means this car never had swirl flaps out of the factory.

Also did wonder if the EGR system/valve might be a bit clogged up. No idea if these have EGR issues but I imagine it's never been cleaned.

The EGR cooler will need to be removed to get to the thermostat. I'm not looking forward to trying to remove any of the bolts around that area. I worry it might turn into a snapped bolt fest city. 😬

Yeah, that intake manifold looks different to the M57s I've had.

Here's a pic from the internet of an engines view of an inlet with swirl flaps, the flaps are in the lower set of runners.

Bonus if you don't have them. I've deleted them on two cars. On my 330d they were pretty fucked so I could see how they could break up and get sucked in, on my 530d the plastic was starting to break up but they didn't seem like they were about to fail in a bad way.

Not a problem you're going to have but also no help to finding your missing power. 

 

 

[SiC]

Fixed* the parking sensors for now. Recoded it to be 4 sensors rather than 8. This disabled the front sensors and now I have beeping rear at least.

I really don't know how the BMW specialist coded out the remote central locking. I couldn't find any coding options in the CAS module that would disable it and I reset the coding back to factory default. Still didn't work.

Had a look at the diversity antenna under the rear spoiler. It's both connected and appears to have power. These are prone to failing but considering RCL was actively disabled, then I'd expected it to have been disconnected.

Fuses are all there including the glovebox fuse board too. So they haven't been pulled.

I did wonder if he deleted the remote central locking data. But if he did that, why not just delete the key that went missing?

I can't think of anywhere else to poke/prod settings for on this to enable it. I'd really like to enable it as I'm so used to having RCL that it's annoying not having it. 

Any suggestions?

[robt100]

4 hours ago, SiC said:

Tbh I think it's just @robt100  🙃.

 

Or my butt sensors aren't as sensitive as Robs!

Yeah, i think I just have a sensitive butt😅

Like I said in the advert, MrsRobt100 doesnt feel it. Back when I did many miles in my octavia, once I'd gone through the first 100k, I could tell which suspension bush was failing/failed just by how it felt. Which is a blessing and a curse when you buy a car, as they all feel a bit broken in some way!

[SiC]

Last night I investigated the dead interior blower motor. Wasn't too bad a job despite what the internet says. Just a bit more than I had to do when I fitted my Mr12Volt Android Auto/CarPlay unit to my 330i. The E90 blower replacement was much easier though - just twist the motor out from under the passenger footwell and it drops out on that.

Getting to it on the E6x does leave the interior looking like this though...

Basically you delve into the area behind the stereo and shift the centre console back after removing a few screws.

Then extracting it out of here and scratching up your hands in the process.

Looking at it, it was obvious why this new unit broke. The brush holder was completely out of alignment. 

Powering it up had it kick into life again.

However I'm not convinced that it's not going to break again. I believe it was only a cheap unit due to circumstances.

Also the TIM (Thermal Interface Material) between the PCB and heatsink in the resistor pack isn't exactly showing much contact area. I don't think it's original and I think it's a cheap aftermarket unit again.

I might buy a second hand fan and resistor pack. They can be had together for about 50 quid and I've always had good luck with second hand blowers. It does mean stripping it all back out again... 😬

It isn't the strongest blower and I imagine this bit will fall out of alignment again in the future. For now it works.

Also stuck the battery on charge as it's pinging low battery warnings almost all the time now. Not sure if these should be AGM batteries or if non AGM are okay? I had this on my Z4 and 330i. The Z4 needed AGM due to that big heavy roof. But the 330i is happy with a standard flooded pack.

A right heavy bugger to get out of the boot.

 

The other batteries are the old ones from my other BMWs 😂

[J-T]

8 hours ago, SiC said:

I can't see any swirl flaps

Part number on the manifold corresponds to this on RealOEM:

 

Which looks like it means this car never had swirl flaps out of the factory.

Also did wonder if the EGR system/valve might be a bit clogged up. No idea if these have EGR issues but I imagine it's never been cleaned.

The EGR cooler will need to be removed to get to the thermostat. I'm not looking forward to trying to remove any of the bolts around that area. I worry it might turn into a snapped bolt fest city. 😬

The EGR cooler/thermostat doofer on top there is shagged if it’s not getting over 70 degrees. It was the same on my 335d; that had had the DPF mapped out but it was probably giving trouble because the ECU would never allow a regen as it was never up to temp. 

[yes oui si]

3 hours ago, SiC said:

 I've always had good luck with second hand blowers. 

Jokes aside, great thread - enjoying seeing you getting stuck into this.

[SiC]

Just been away in India with work last week but before then I replaced the thermostat on this with a new Febi unit. I didn't do the EGR thermostat as looked new (branded BGA) and getting to 70c which it's opening temperature.

Top cover off the rads

Blower out 

Removed EGR cooler - was a right bugger as some were hex and some were torx fasteners.

I was nervous about these bolts but they came out without a problem. I have to say, this era BMW used high quality fasteners and I very rarely had any issues removing them on all I've owned.

EGR was dirty but not awful considering the mileage.

Still worked though. I did give it a proper clean afterwards.

Turbo looks in good shape and felt good. The bits of carbon I did clean off before putting everything back together after.

 

Thermostat wasn't too bad once I got everything out of the way.

Thermostat was definitely buggered with all it's magic juices leaked out of it

Date coded 2007 so original to the car

Then reverse of the above to put this pile of fasteners back in. Imo far longer to do a thermostat than most other cars of this era.

Then refilled the coolant. This has an auxiliary water pump, so bleeding was as simple as turning on the ignition and let that pump circulate. Occasionally opening the bleed valves to let the air out.

Ran it up to temperature 

Went for a drive. As I got back it progressively got cooler. Lowest I saw it hit was 70c.

FFS the new thermostat is buggered already.

I've ordered a new genuine BMW engine thermostat and a Mahle/Behr (so OEM) EGR thermostat. So I need to do this all again.

sigh

 

I started fiddling with INPA (BMW factory diagnostic tool) to see if I could get the remote central locking working again. One option I saw in the Car Access System module was resync and a load of German. Gave it a go.

Failed half way as it didn't recognise the Engine ECU. 

Then would no longer start and had this error code.

Uh-oh! Did I now just brick it?

 

After a stressful hour I found an updated version of INPA. In this version I could access the engine ECU and trigger a EWS delete + resync in the options. Gave that a go.

Engine now starts

Phew!!

Lack of Remote Central Locking really pisses me off. Not sure how I can fix it as I have no idea what the specialist did to disable it. Doesn't seem to be coded out in any module and the antenna appears functional. Might speak to a Auto Locksmith and see if they have any tricks up their sleeves.

Also I've bought a cheap glow plug module to clear the glow plug codes as I believe that is usually the cause. It won't regen with those codes either. 

[Bren]

The condition of the EGR  speaks volumes for the cars maintenance and how it has been used.

Shame about the thermostat. So many poor parts around.