My 2006 Z4 Coupe
- Thread starter STC_Zed
- Start date
Meds said:Nice work, Sam..
I keep thinking to do mine in Montego Blue, not a DIY, my paint man would do a good job for me.
But, it might look a little garish.
I think it could look really good. The trim options on these are so restricted and there aren’t many used ones knocking about.
More catch up posts on my E86…
First up, I decided to tackle the slightly manky headlights which let the side down a bit. They’re better but there’s still room for improvement.
I tried to capture how bad they were up close, but the sun wasn’t helping.
Masked up ready to be sanded
Part way through sanding. The water running off the light was very, very yellow.
Once sanded with 800 grit, 1200 grit and 3000 grit, the lights were buffed with a heavy compound and and a finishing compound before because sparked with Meguairs UV sealant. The strong sunlight made it difficult to get any decent pics.
I might redo them later in the year and use a 2k lacquer to protect them instead.
First up, I decided to tackle the slightly manky headlights which let the side down a bit. They’re better but there’s still room for improvement.
I tried to capture how bad they were up close, but the sun wasn’t helping.
Masked up ready to be sanded
Part way through sanding. The water running off the light was very, very yellow.
Once sanded with 800 grit, 1200 grit and 3000 grit, the lights were buffed with a heavy compound and and a finishing compound before because sparked with Meguairs UV sealant. The strong sunlight made it difficult to get any decent pics.
I might redo them later in the year and use a 2k lacquer to protect them instead.
Next up was changing my CCV. Since I’ve had the car, I’ve noticed that it’s got through about a litre of oil every 1,200 miles. All of the gaskets on the top of the engine were done shortly before I bought it. The sump is weeping (would it be a BMW if it wasn’t leaking oil from somewhere? :wink: ) but as pointed out on another forum, if it was leaking that much oil then my drive would be a mess, which it isn’t). A failed CCV is often the cause for oil consumption because the vapours get burnt rather than returning to the sump. I happened to have a Febi CCV kit that I’d built for my wife’s 330i but since my car uses more oil, I decided my need was greater than hers. What should have been a relatively straight forward job turned out to be a complete ball ache (mainly because of user error 
).
Luckily in the Z4, there’s much more room than in my previous N52 powered cars).
I started disassembling the intake manifold, labelling connectors as I went.
Soon the manifold was free and I could lift it up to see the CCV connections
With the old CCV free, I had a quick look at the pipes removed and they were really gunked up as was the old CCV.
Old and new CCV
New CCV fitted with new manifold gaskets.
In went the manifold and I starting connecting everything back up.
I started the car and that’s when it all went wrong….
).Luckily in the Z4, there’s much more room than in my previous N52 powered cars).
I started disassembling the intake manifold, labelling connectors as I went.
Soon the manifold was free and I could lift it up to see the CCV connections
With the old CCV free, I had a quick look at the pipes removed and they were really gunked up as was the old CCV.
Old and new CCV
New CCV fitted with new manifold gaskets.
In went the manifold and I starting connecting everything back up.
I started the car and that’s when it all went wrong….
I started the car and it was barely running. It would fire up and stall straight away. s**t. At this point the light was fading so I called it a day and went inside for a beer.
The next day it was time to start checking all of my connections. The small DISA plug didn’t seem to sit all the way in so a quick fiddle with that and still nothing.
I the started to look at the CCV pipes because that’s what had been changed. The new oil return pipe didn’t seem to click into place like the old one, so that was cleaned up and reinstalled. But nope, still wouldn’t run.
I did discover that it’d run with the MAF unplugged so I started to wonder if that’d had been damaged somehow. A new MAF was tried but nope.
After lots of head scratching and checking things, I found this
There is a vacuum line behind the throttle body which had been an absolute sod to get off and it was even harder to get bs I in place. This was the cause of my vacuum leak.
Out came the manifold again and I removed that vacuum line form they car make it easier to get properly connected to the manifold again.
Here’s a picture of the old CCV too. Gunky.
I also discovered the hard way that the sounder generator box needs to be con for the car to run properly. The car was now starting and idling just fine but I had a check engine light on. FFS.
The car drove just fine so I was scratching my head (still). It was at this point that my Carly app decoded to s**t itself and it refuses to complete a code read. It reaches 90% and just stops. To try and understand is going on, I bought a Creator code reader which arrived promptly courtesy of Amazon Prime. I’m left with these four codes.
Initially thinking that the car running rich with no MAF I wondered if a load of fuel had been dumped into the exhaust, killing the O2 sensors. Fearing the worst, I start looking at the cost of new ones and getting a bit of a shock I ran off to Google. The chances of all four sensors dying at the same time looked really slim and a few threads mentioned that it could be a fuse. This lead to much more time on the internet and I eventually found a list of fuses in the engine bay. Fuse four is for the CCV heating and Ow sensors….
One blown fuse. I’ll be heading to ECP soon to collect a box of fuses which will hopefully resolve the issue once and for all.
The next day it was time to start checking all of my connections. The small DISA plug didn’t seem to sit all the way in so a quick fiddle with that and still nothing.
I the started to look at the CCV pipes because that’s what had been changed. The new oil return pipe didn’t seem to click into place like the old one, so that was cleaned up and reinstalled. But nope, still wouldn’t run.
I did discover that it’d run with the MAF unplugged so I started to wonder if that’d had been damaged somehow. A new MAF was tried but nope.
After lots of head scratching and checking things, I found this
There is a vacuum line behind the throttle body which had been an absolute sod to get off and it was even harder to get bs I in place. This was the cause of my vacuum leak.
Out came the manifold again and I removed that vacuum line form they car make it easier to get properly connected to the manifold again.
Here’s a picture of the old CCV too. Gunky.
I also discovered the hard way that the sounder generator box needs to be con for the car to run properly. The car was now starting and idling just fine but I had a check engine light on. FFS.
The car drove just fine so I was scratching my head (still). It was at this point that my Carly app decoded to s**t itself and it refuses to complete a code read. It reaches 90% and just stops. To try and understand is going on, I bought a Creator code reader which arrived promptly courtesy of Amazon Prime. I’m left with these four codes.
Initially thinking that the car running rich with no MAF I wondered if a load of fuel had been dumped into the exhaust, killing the O2 sensors. Fearing the worst, I start looking at the cost of new ones and getting a bit of a shock I ran off to Google. The chances of all four sensors dying at the same time looked really slim and a few threads mentioned that it could be a fuse. This lead to much more time on the internet and I eventually found a list of fuses in the engine bay. Fuse four is for the CCV heating and Ow sensors….
One blown fuse. I’ll be heading to ECP soon to collect a box of fuses which will hopefully resolve the issue once and for all.
Since my last post, I’ve changed the fuse but the engine management light keeps making an appearance. It’s not there after clearing the codes but on the start after that, it makes an appearance and brings back the codes for all four lambda sensors. Other than this the car is driving just fine.
I checked the fuse again today and it had blown. I’m starting to think there is an electrical issue with the CCV heating because it’s on the same circuit as the O2 sensors.
At lunchtime today, I did some more fiddling and may have found the source of the vacuum leak giving me a rough idle.
This part of the sound generator wasn’t fully seated in the plastic bracket. I remove the intake pipe and the backer and got it to seat properly; getting it to do so too a bit of effort off the car which is why I may have ballsed up previously. I’d really not thought that the sound generator would be that integral to the intake system. I’ll find out at 3pm if this has solved my slightly rough idle.
Some googling revealed that there are quite a few cases of the fuse for the CCV heating and O2 sensors being tripped and the common culprit seems to be the CCV heating. I’m now trying to establish which one(s) are causing me grief. To start with, I’ve unplugged the CCV heating power cable first. If it is this one, I’ll be really pissed off because it’s a new part. If the fuse blows again, I’ll plug it in again and remove the plug below it etc etc. I want to identify which one is at fault rather than load the part cannon.
There is a chance one of the pins in the plugs has been damaged on the power box, it’s probably not hard to do when you’re plugging things in by feel unsighted. The part isn’t expensive but will require the manifold being pulled (again).
I checked the fuse again today and it had blown. I’m starting to think there is an electrical issue with the CCV heating because it’s on the same circuit as the O2 sensors.
At lunchtime today, I did some more fiddling and may have found the source of the vacuum leak giving me a rough idle.
This part of the sound generator wasn’t fully seated in the plastic bracket. I remove the intake pipe and the backer and got it to seat properly; getting it to do so too a bit of effort off the car which is why I may have ballsed up previously. I’d really not thought that the sound generator would be that integral to the intake system. I’ll find out at 3pm if this has solved my slightly rough idle.
Some googling revealed that there are quite a few cases of the fuse for the CCV heating and O2 sensors being tripped and the common culprit seems to be the CCV heating. I’m now trying to establish which one(s) are causing me grief. To start with, I’ve unplugged the CCV heating power cable first. If it is this one, I’ll be really pissed off because it’s a new part. If the fuse blows again, I’ll plug it in again and remove the plug below it etc etc. I want to identify which one is at fault rather than load the part cannon.
There is a chance one of the pins in the plugs has been damaged on the power box, it’s probably not hard to do when you’re plugging things in by feel unsighted. The part isn’t expensive but will require the manifold being pulled (again).
Meds said:Superb troubleshooting, Sam!!
Hopefully the new fuse and a code clear and you're done!
You recommend the Creator reader? I'm in the market for one.
I forgot to answer your question re the Creator.
So far, I can’t really fault it. It feels a bit cheaply made but it wasn’t expensive to start with! I’ve been struggling to get Carly to work whereas this fires up every time and seems to clear the codes as needed. It seems like a good bit of kit and was delivered quickly via Amazon.
Mr Tidy said:I had hoped you'd got it all sorted Sam!
Anyway good luck tracking down what is hopefully the last remaining issue - and it's good to see your safety footwear make an appearance on here.
Thanks. I think I’m on the right path (the fuse blew again tonight). The pipe from the valve cover is plugged back in and I’ve unplugged the oil return heater. We’ll have to see what happens tomorrow.
I still have a slight flutter on the revs upon start up, so I can only assume that I have a slight vacuum leak somewhere.
In other good news, the passenger side head light washer shat itself tonight and emptied the contents of my washer reservoir onto the drive. Looks like I need to track down a used one or fine away to stop the fluid leaking out (they’re turned off anyway).
STC_Zed said:
I had that problem with my current Z4 that had a leaking passenger side one when I bought it in 2019. Managed to find a used pair on here so replaced it and pulled the fuse.
But earlier this year the passenger side one was leaking again. Luckily the used ones came with the pipework so I disconnected the pipe from the pump, attached a short piece of pipe and screwed a bolt into it!
I've never been unable to see due to dirty headlights, but on an unlit road at night that you don't know when they operate visibility gets to be guesswork. They're a pointless PITA!
STC_Zed said:
I can't remember precisely what I did to my first E86, but pretty sure I pulled the headlight washer pump from the washer tank, placed a piece of clear plastic (plastic bag or clingy film) between the tank and the pump and that stopped the lines inside the bumper leaking. Like yours, mine were deactivated, but I think there is still a pressure head that can cause most of the fluid to leak out.
Mr Tidy said:
lucasxdiniz said:
Thanks both.
It looks like it’s leaking from from the nozzles / jets which is irritating.
I think I’m going to either try and cap it off at the reservoir end or possible replace the but a used reservoir from a car that didn’t have headlight washers. Looking on eBay they’re cheap enough.
STC_Zed said:
I have a fluttery idle on start, I did on the 130i LE, too.. For about 15secs or so.
I thought a good way to test for vacuum was to slowly open the oil filler cap while idling, if air rushes in and there's resistance to opening, then the CCV/valve cover has good negative pressure.
It wont help track it down, but might be a good quick test to see if you do have pressure, or not.
But, I might have imagined reading that somewhere and talking absolute nonsense.
Meds said:STC_Zed said:
I have a fluttery idle on start, I did on the 130i LE, too.. For about 15secs or so.
I thought a good way to test for vacuum was to slowly open the oil filler cap while idling, if air rushes in and there's resistance to opening, then the CCV/valve cover has good negative pressure.
It wont help track it down, but might be a good quick test to see if you do have pressure, or not.
But, I might have imagined reading that somewhere and talking absolute nonsense.
My 130i did too. My wife’s 330i is rock solid though.
Warm idle is fine though. It’s booked in on the 9th for some investigation because I can’t see anything obvious now.