[Opo]

2008 BMW 335i Canadian car
N54 (no oil cooler, furious about this lol..)
JB4
BMS DCI
BMS DP
BMS oil catch can

Hello,

I'll start by saying I have read through multiple wastegate rattle, fuel pump, vacuum line threads on these forums and they have been pretty helpful but I haven't been able to find a 100% accurate reason for these codes..

I have a 3rd party warranty, as I bought the car used. It expires in another 8000 miles approximately.. I just had my water pump replaced under warranty a few days ago. Back in February I had 1 ignition coil, and 3 injectors replaced under warranty due to a misfiring issue, along with a thermostat and spark plugs.

Yesterday I went to a local track (road course), my first 3 sessions went really well, no issues with the car at all. On my 4th session I got a big CEL in the small display area, half filled with yellow. When you check the status on it, it displays CC-ID 29. I have only been able to find very vague information about the causes of CC-ID 29.

The car also displays SERVICE for a second when started now and it has never done that before.

I plugged my laptop into my JB4 to check the codes and I had codes

3100 low boost mode engaged -- CEL displayed
30FE Boost over target

The car does not have any genuine OBD2 CEL codes thrown (shown by the small CEL in the regular spot..)

This is the weird part... The big CEL light half lit up yellow would clear itself (even with auto-clear DISABLED) and I would have full boost pressure again, when it was on the car would struggle to give me 2-3 PSI.

The car was going into this limp mode state on map 1 and map 5, it also still went into this mode even with the JB4 completely disabled!! so the JB4 is not causing it.

I also now have some extreme wastegate rattle noise, see this video:

I drove the car today all over town and on highways going WOT in 1st, 2nd, and 3rd gear with the JB4 completely disabled trying to trigger the limp mode again and it would not do it, it ran perfectly fine @ 6 PSI with the exception of throwing genuine OBD2 codes P0420 and P0430 due to the cat-less down pipes.

I'm not sure what to look toward next, should I be looking for vacuum leaks?
But if its a vacuum leak why would it come and go on its own like that? shouldn't it be constant.. and shouldn't it have triggered today driving around with the JB4 disabled..

Originally I was going to just take all my mods off except the down pipes and take it in for a warranty repair claiming the obsessive wastegate noise issue, but want to hear what else has to be said about this issue.

[N55guy]

My vacuum leak was not constant... Only had issues at the track and on a dyno. I had a very small leak near the oil filter. Id start by changing vacuum lines out, it's cheap and not hard to do.

[e46m3to335i]

I would take the DP's off if you plan on having the wastegates checked out.

[Opo]

Can a vacuum leak cause the 30FE code tho? I thought it could only cause the 30FF or whatever?

[E90Company]

Originally Posted by Opo

Can a vacuum leak cause the 30FE code tho? I thought it could only cause the 30FF or whatever?

30FE would normally be caused by turbo v-band clamps blocking wastegate arm travel, clogged vacuum canisters, or faulty boost solenoids. Vacuum leak won't cause it.

[Opo]

Okay that is a big help I'll keep digging. I did the down pipes myself and didn't pay much attention to the vband clamps so that's possible.

The vacuum canisters, I'm assuming you're referring to the 2 cylinder ones right by the turbos that connect to the wastegates? How can I clean them?

[yawn]

I have exactly the same problem as the OP bar wastegate rattle. 30FE only comes up on the track, not during daily use.

Just wondering though, if the v-band clamps on the DPs are blocking the wastegates, that would mean the wastegates are shut - so that creates the overboost? And if they are open (for example there have been mentions of sticky wastegates that require grease to be relieved), then there is the 30FF code for underboost?

[Tiago@VRSF]

I'd check the DP alignment, that sounds way too loud to be WG rattle unless something is actually broken.

[vanondemand]

I used to get 30FE codes due to the previous owner of my 07 335i doing a solenoid boost bypass on my car. Took me months to figure it out till I looked closely at my solenoids and realized that one of them was inactive with the vacuum hose bypassed. Checked that if you haven't and if not maybe your solenoid has gone bad.

[yawn]

If a solenoid has gone bad, doesn't that mean that the wastegates stay open? The way I understand it is that the solenoid is responsible for closing the wastegates. By default, the wastegates are open. So when building boost, the solenoid will activate to close the wastegates to allow boost to be built up.

If the solenoid was bad, that means the wastegates are left open, which will result in underboost and 30FF not 30FE code. Correct?

[yawn]

Unless when you mean bad solenoid, you mean malfunctioning solenoid as it sends a prolonged signal to close the wastegates longer than it should, resulting in overboost conditions?

[Opo]

Soooooo...

whatever happened to my car is getting weirder and weirder.

The night after the track night I went outside and started the car, disconnected the vacuum canisters on the top, and reconnected them. and VOILA my intense waste gate rattle vanished just like that. Just be disconnecting and reconnecting the vacuum canisters.... so I never ended up taking it in for warranty service.

The next day my friend and I took the car out and did 10+ runs from 0 to topping out 4th gear trying to get the problem to trigger while we were data logging and we could not get it to show up again!

We also tested my boost solenoids by following the steps in this video here:

and both tested out perfectly fine.

We took out my vacuum canisters and both are holding vacuum just fine, we pumped them up to see if they would leak but nothing... they held fine until we unblocked the bottom port.

And we checked the downpipe clamps from up top and could not see how they would be blocking the waste gate arms at all. We are yet to check from underneath the car...

So I still don't know what the hell ruined my one night at the track.. my current plan is to go to the track again and see if the problem arises again and this time make sure to data log it.

Any other suggestions?

btw: neither of my boost solenoids were bypassed..

[Opo]

Oh and when we were doing the 10+ runs 0 to topping out 4th gear I was running firmware 23 on my JB4 G5. The logs from this night I have all saved on my computer but haven't really looked at them/had anyone look at them.

I have since opened up my JB4 and cut the diodes and upgraded to ISO 25 firmware.

[ratfranco]

Hello, I know that is being more than an year that this thread was opened but my car seems to have the same issues. did you find out the solution? Thanks

[Opo]

boost solenoids