[Brule]

I was giving the adjustment on jb4 as an example of tuning that can be done on any flash as well.

If its not tuning, have you reset any throttle o2 etc with a bt cable?

[harms]

Update:

I've either made things much worse, or have finally found some solid direction...

I cleaned both vanos solenoids today with a bit of carby cleaner.
I actually replaced the exhaust solenoid around 1 year ago, so I decided to put this in the Intake (top hole) and the older one in the Exhaust spot to see if it started throwing codes.

Well low and behold the car is now throwing codes, but the bad news is that it now barely runs/idles. Once it throws a limp mode then it seems to idle ok but I assume that is because its running different settings.

It is throwing code 2A82 Inlet-Vanos variable cam control test, even though I put the newer solenoid in the Intake spot.

It once threw 2A98 Crank shaft - Inlet camshat correlation, however it is mostly 2A82.

So I guess my next move is to replace both solenoids to see if this fixes everything. But i find it really strange that the car is barely running. It is like the Intake solenoid isn't plugged in properly (I have checked this a heap of times)

[vtl]

That doesn't sound right. When I cleaned the solenoids I forgot to plug one back in and the car actually idled fine. I gave it a rev and it threw a vanos code. Plugged it back in and all good. It's not possible you got the connections swapped?

[harms]

Thanks Vince that is exactly what I did! Swapped the plugs around and its running fine now. BMW even made 1 plug right angled and I still mixed them up!

Switched the good solenoid over to the intake again to see if this changes the surging.

Unfortunately the surging is still present. However it feels like it isn't as bad, but it might be my imagination. I'll try this out for a few days to see if it really feels improved or not before ordering new solenoids.

Originally Posted by vtl

That doesn't sound right. When I cleaned the solenoids I forgot to plug one back in and the car actually idled fine. I gave it a rev and it threw a vanos code. Plugged it back in and all good. It's not possible you got the connections swapped?

[CYL]

Sorry, off topic
But may I ask if there is any DIY for replacing the vacuum lines?
What I can find on the internet is only people talking about changing it to silicone hose but no actual DIY section.
I know it's simply unplug and plug the hose but I am not sure how many vacuum lines are there..

Also I read that people saying don't bother those vacuum lines behind the engine or wastegate and only do those ones on top of the engine, is it true?

Any silicone hose from SCA will do? May I ask what size should I get?

Thanks.

And wish you all the best and solved the problem soon Harms.

Originally Posted by vtl

Have you already replaced all your vacuum lines? Long shot since its at low rpms and your logs don't seem to indicate the boost correlates with the oscillation but worth ruling out.

I'd say O2 sensors are next on the list if they've never been replaced. O2 sensors have a zirconia element which gets depleted over the course of normal operation. I'd say if you were 120k+ they might be on their way out but might be less depending on conditions.

Vanos solenoids I'd be surprised if they were the cause if you're not throwing codes and the car is pulling good to redline. Just give them a clean since its doesn't cost anything. I ran carby cleaner through them while energizing them with a 12V power supply. Didn't notice any difference but good to know they're good.

[vtl]

Originally Posted by CYL

Sorry, off topic
But may I ask if there is any DIY for replacing the vacuum lines?
What I can find on the internet is only people talking about changing it to silicone hose but no actual DIY section.
I know it's simply unplug and plug the hose but I am not sure how many vacuum lines are there..

Also I read that people saying don't bother those vacuum lines behind the engine or wastegate and only do those ones on top of the engine, is it true?

Any silicone hose from SCA will do? May I ask what size should I get?

Thanks.

And wish you all the best and solved the problem soon Harms.

Read this thread, it has the exploded diagram of the hoses and tip and tricks on how to do it all
http://www.e90post.com/forums/showthread.php?t=894084

This is the realoem link
http://www.realoem.com/bmw/enUS/show...diagId=11_3975

You want 3.5mm vacuum line, this is a local source for the braided stuff:
http://www.justkampers.com.au/n02035...1-2-meter.html
I bought 3 metres

I couldn't find a good source local for 3.5mm line so I went FCP euro when I was buying a bunch of other stuff:
https://www.fcpeuro.com/products/bmw...er-11727545323

Its hard to find 3.5mm smooth hose locally so a lot of people go 4mm instead. I can't say I agree with this because they don't stay on the nipples as tightly and the larger diameter makes them not fit in the hose clips properly. Just do it properly and buy the correct diameter.

Ideally replace ALL lines, the turbo wastegate braided lines are the most difficult but they are the ones subjected to the most heat. I did notice better boost response after changing out my lines. Make sure you slice the lines with a scalpel because the rubber tends to stick to the nipples. You could easily break the plastic nipples trying to get the rubber lines off.

[CYL]

Thanks VTL
I eventually found that said DIY post last night too.

Can I just use the vacuum lines from FCPeuro for all the area including the wastegate?

And I read that people are replacing with silicone hose. The FCPeuro doesn't seem to be silicone?
Actually, is rubber or silicone better?
I also read that silicone is actually must more prone to crack than rubber hose, true?

Originally Posted by vtl

Read this thread, it has the exploded diagram of the hoses and tip and tricks on how to do it all
http://www.e90post.com/forums/showthread.php?t=894084

This is the realoem link
http://www.realoem.com/bmw/enUS/show...diagId=11_3975

You want 3.5mm vacuum line, this is a local source for the braided stuff:
http://www.justkampers.com.au/n02035...1-2-meter.html
I bought 3 metres

I couldn't find a good source local for 3.5mm line so I went FCP euro when I was buying a bunch of other stuff:
https://www.fcpeuro.com/products/bmw...er-11727545323

Its hard to find 3.5mm smooth hose locally so a lot of people go 4mm instead. I can't say I agree with this because they don't stay on the nipples as tightly and the larger diameter makes them not fit in the hose clips properly. Just do it properly and buy the correct diameter.

Ideally replace ALL lines, the turbo wastegate braided lines are the most difficult but they are the ones subjected to the most heat. I did notice better boost response after changing out my lines. Make sure you slice the lines with a scalpel because the rubber tends to stick to the nipples. You could easily break the plastic nipples trying to get the rubber lines off.

[vtl]

Originally Posted by CYL

Thanks VTL
I eventually found that said DIY post last night too.

Can I just use the vacuum lines from FCPeuro for all the area including the wastegate?

And I read that people are replacing with silicone hose. The FCPeuro doesn't seem to be silicone?
Actually, is rubber or silicone better?
I also read that silicone is actually must more prone to crack than rubber hose, true?

The FCP lines are silicone, I have purchased them and fitted to my car. Silicone should last longer than rubber, overall it should be superior in longevity.

The downside is that they are quite soft and you can sometimes kink them if installed incorrectly. I would not use them to replace the braided lines. I'd use the braided stuff to replace the braided lines as they hold their shape better and wont get squished in the hose clips. Make sure you replace the braided lines that go accross the top of the engine (the two lines that go from the plastic hard pipes to the vaccuum pump tube)

Better start your own thread if you have more questions to keep Harm's thread on topic.

[harms]

I have a new theory on my issue...

Someone over on 81mmer800st did of a log of their car under the same partial throttle conditions where I get the issue. They have stable everything, lpfp, hpfp, stft's, afr's.

When comparing to my log, I have oscillating afr's, stft's, hpfp. But lpfp is ok. So something might be going on between the lpfp and the hpfp??

So, I've ordered a new hpfp sensor. My theory is that the sensor has crapped itself and not registered steady pressure under these conditions. The DME is compensating with increasing stft, which then richens the afr. Then it bounces the other way by decreasing stft. Therefore causing the surging feeling.

Just an idea. The sensor isn't expensive, so worth a try.

Stay tuned...

[Socket]

Hope you get this sorted mate

[harms]

Update:

Replaced the HPFP sensor today. No luck.

Back to square one.

This car deserves Coles engine oil. Yes they sell their own oil, WTF?

[Scotty89]

Have you tried disabling the boost and seeing if the oscillation is still there?

Maybe drive with vacuum tanks unplugged (half engine mode), and see if it still occurs. I think it will be something to do with vacuum for boost control.

[DR-JEKL]

Vanos solenoids pre cat o2 sensors worked for me

[JRAD7]

I had to replace both vanos solenoids. Best way to check if they are causing issues is to find a reasonably steep road and put the car into 3rd or 4th gear at around 2k rpm and go wot. If it's vanos the car will oscillate and throw a code after about 3-5 seconds. It feels like micro second interruptions in the power band. If it does throw vanos codes just replace them both. Not worth messing around and cleaning etc. Cleaning doesn't fix it for long. Buy them online from ecs and install yourself to save a lot of money.

[JRAD7]

I forgot to mention also...right before I got them changed under stat warranty the car was iddling really rough and hardly ran. It was only on one or two occasions but sounds very similar to your experience.

[harms]

Originally Posted by Scotty89

Have you tried disabling the boost and seeing if the oscillation is still there?

Maybe drive with vacuum tanks unplugged (half engine mode), and see if it still occurs. I think it will be something to do with vacuum for boost control.

Good idea mate. I tried this and no luck.

Here is a log running with vac canisters unplugged.
http://datazap.me/u/harms/throttle-o...27&zoom=42-200

I was surprised other than this issue, the car ran alright with boost disabled. No limp modes, no error codes. The boost gauge ran varying levels of vacuum, but when accelerating it when to 0 psi boost.

[harms]

Originally Posted by JRAD7

I had to replace both vanos solenoids. Best way to check if they are causing issues is to find a reasonably steep road and put the car into 3rd or 4th gear at around 2k rpm and go wot. If it's vanos the car will oscillate and throw a code after about 3-5 seconds. It feels like micro second interruptions in the power band. If it does throw vanos codes just replace them both. Not worth messing around and cleaning etc. Cleaning doesn't fix it for long. Buy them online from ecs and install yourself to save a lot of money.

Thanks for the advice mate.

I've cleaned and switched the vanos solenoids with no improvements, so I'm not convinced it's them.
I actually have zero problems under any WOT conditions, high or low load, hot or cold, all gears fine. No codes ever. It's just when at ~10% pedal position cruising gently at the same speed between 1.5-2k rpm I have this issue. So strange.

[harms]

Originally Posted by DR-JEKL

Vanos solenoids pre cat o2 sensors worked for me

I've ordered some O2 sensors. I will report back when they are installed.
Worst case scenario I'll have new O2 sensors.

[polskatomek]

fouled spark plugs? MAF sensor dirty? I had an oscillating idle issue recently (before & after getting an update to my Active tune), and getting adaptation reset on INPA seems to have helped greatly, although there is still a slight blip at idle that I attribute to a not quite perfect tune.

[harms]

Good suggestions.

Plugs are almost new, i've inspected them they look pretty good.
Both MAP sensors are new too (335i's don't have MAF's).

I'll be putting in new O2 sensors this weekend which i'm hoping is it!

Originally Posted by polskatomek

fouled spark plugs? MAF sensor dirty? I had an oscillating idle issue recently (before & after getting an update to my Active tune), and getting adaptation reset on INPA seems to have helped greatly, although there is still a slight blip at idle that I attribute to a not quite perfect tune.

[vtl]

Originally Posted by harms

Good suggestions.

Plugs are almost new, i've inspected them they look pretty good.
Both MAP sensors are new too (335i's don't have MAF's).

I'll be putting in new O2 sensors this weekend which i'm hoping is it!

Get them in on saturday so you can make it to Winton!

[harms]

So the O2 sensors haven't fixed the problem. Fiddlesticks.