[Blitzsah]

Originally Posted by WillLowe

From memory mine was still moving fine and I was told by 2 bmw techs it wasn't the issue. I did notice a clicking noise from the actuator when turning the engine off though.

After replacing various other parts which didn't solve the issue including a new DDE which wasn't cheap (because the actuator was DEFINITELY fine according to bmw) I swapped over the actuator with a friend and law and behold his car inherited my power loss and mine was fixed. I'm not saying this is definitely your issue but it's certainly the same symptoms I had so worth a shot if you can get someone local to let you try the swap.

Thanks, think I’m just going to risk it and order a new actuator anyway.

I’ve spent so much already trying to get to bottom of the issue what’s another £150…

[dheimans]

Good afternoon all,
I’m new on this forum, but I do have exactly the same issue with my F31 335xd.
So far I bought new turbo’s (got tuned hybrid upgrade), new ecu, new inlet manifold, replaced all sensors, wires, vacuum lines and many more and the problem is still not solved!
DPF is fine. EGR is fine.
Log says turbo is not building up boost, lags 1 bar.
What my current BMW specialist in the Netherlands found out is that the ECU is not switching from the small to the big turbo. If we test the valve, we are able to switch. That works perfectly fine, but once on the road the valve is not switching. The result is loss of boost after 3.000rpm.
My car is at this point 4 months in the garage and I have paid around €12.000,- on parts and labor.
BMW Netherlands is involved as well and they have no clue. The last advice was to buy a new ecu (so I did), but this didn’t help…
Do you guys have any idea?
Thanks in advance!

[Elevator]

Im having the same issue in my 11 335d, normal power ramp up from 1500 untill 3k, then it feels like all boost cuts out and looses all power, Im relatively new to messing with this car so I dont really know where in the engine bay anything is yet, so when you do figure it out I would love some pictures.

[Blitzsah]

The actuator I bought from eBay arrived yesterday.

Do these need calibrating for my specific turbo or will it work out the box? I don’t want to fit it and then it cause damage to turbo etc…

[WillLowe]

It will work out of the box. AFAIK the actuator is only hardware and is controlled by the ECU

[Blitzsah]

Quick update, the actuator is replaced and the issue remains.

No idea what to do now, will send to a specialist I think

[dheimans]

Dear Blitzsah,

The part you have replaced is the actuator for the VTG (Variable Turbo Geometry).
The 335d has two turbo's. The small turbo for low RPM's is equipped with VTG, the big Turbo (for High RPM's) has no VTG.
So the part you have changed will never affect the power band above 3.500rpm...

[dheimans]

Above you see the power curves of my 335xd.
The Blue line is the graph of the car with original software, new hybrid turbo's, Wagner Intercooler, new inlet manifold and many more small parts.

The Brown line is everything above and a brand new CDU/DDE

The Red line is everything above without a DPF.

At this moment my DPF is send away to be cleaned. Hopefully next week it will come back and I will have some new results... I'm still a bit sceptic because we are missing almost 100bhp!

[Blitzsah]

Originally Posted by dheimans

Attachment 2759279

Above you see the power curves of my 335xd.
The Blue line is the graph of the car with original software, new hybrid turbo's, Wagner Intercooler, new inlet manifold and many more small parts.

The Brown line is everything above and a brand new CDU/DDE

The Red line is everything above without a DPF.

At this moment my DPF is send away to be cleaned. Hopefully next week it will come back and I will have some new results... I'm still a bit sceptic because we are missing almost 100bhp!

Any news on this?

Update from me is the car is still the same, in fact with the new actuator I don’t get a drive train warning light anymore but it now stutters in the low rev range too. Suspect it’s due to the fact this actuator was not calibrated to this car. Will probably re fit the old one at some point…

So tired of this now

[KoktGrus]

Got exactly the same problem on my 535d 2014.
Replaced vacuum lines, valves and pressure converters without success…

Small turbo making some whine in idle. But it follows the requested boost fine. Then at about 3200 rpm boost drops to like zero.
This is at the point where the turbine control flap changes over and the large turbo should “take over”.

As I see you have replaced both turbos it breaks my theory that it could be the large turbine.
No idea if the actuator for turbine control flap was renewed?
I checked mine and it moves, so I think it’s ok.

[Blitzsah]

Actual boost vs requested boost, this is from today from standing start foot to the floor up to about 50 mph.

[Watsey]

Originally Posted by Blitzsah

Actual boost vs requested boost, this is from today from standing start foot to the floor up to about 50 mph.

Sorry to state the obvious, but it would be useful to see the rpm on that plot.

Looking at the boost curve it's 'got' to be related to the transition from small>large turbo.

The plot does indicate that the ECU is calling for boost, which suggests that a mechanical problem is the root cause. I'm not particularly knowledgeable about the sequential turbos as my 30d has a single turbo.

If you want a BMW specialist indy to talk it through with, I can recommend Phil Crouch (CPC Performance Engineering; Amersham, Buckinghamshire - 01494 766661‬). Phil has worked on my car a few times now, including turbo replacement, and really does know his stuff. He is always extremely busy though, and sometimes you have to be patient in terms of a call-back. Have a chat with Katy or Anjali who manage the phones / reception / bookings.

[dheimans]

Hi guys,
I just received a phone call from my garage the other day.
They might have found a possible solution!
For this engine type there is a problem with some EGR valves.
The valve is a tiny bit too large and therefore unable to reach it’s 100% position. As a result the valve is not responding and prevent the ecu to build op boost on the large turbo (due to possible engine damage). There is no fault logged and even if the EGR is written out of the software the problem still exists on the background!
Today my new EGR is arriving and hopefully I will have good results at the end of this week.
In the mean time my super clean DPF is back in without any result. So at the end I do have a clean engine. Once again, I really do hope this is it after searching for almost 8 months…

[Blitzsah]

Sorry I forgot to add the rev count to the graph.

The EGR was the first thing that BMW replaced for me, which made absolutely no difference so I really hope it fixes it for you but I’m not convinced.

My car is booked in next week at a bmw specialist so let’s see if they can find anything wrong with it.

[dheimans]

Good afternoon guys,

I've got my car back and the problem is still not solved unfortunately...
The EGR was replaced and programmed correctly, but the big turbo doesn’t spool up…
I have the “check engine light” on now combined with the 244C00 - Charge-air pressure control, control deviation: charge-air pressure too low
How is your car doing Blitzsah?

[rasa bmw]

my 640d has had a boost prob for like 11 months,only happens at 130mph and over.goes to limp with drivetrain warning etc,changed boost sensor,seemed to cure it,but came back,new pressure converters for turbp's,still the same,but did manage a run to 140 mph and no limp mode.it has been remapped during covid by bwchiptune,i sent him my ecu as full lcokdown in may 2020,,,my bmw indy.ex tech is now,and was saying from the start it could be a map problem,but i dismissed this as jason at bwchiptune is very well respected and i have chats with him,anyway im getting this map taken off on saturday and indy is putting a celtic tune on it,he said he thinks its making to much boost,ive had loads of different codes that come and go from dpf differential pressure to charge air leak at idle etc etc.please update as this topic is interesting

[Blitzsah]

Got rid of the car in the end.

Couldn’t be bothered spending any more money on it. I took it to a specialist and they told me the turbos needed sending off again for refurbishment which I wasn’t prepared to pay for.

Won’t be buying another bmw anytime soon.

[Watsey]

Originally Posted by Blitzsah

Got rid of the car in the end.

Couldn’t be bothered spending any more money on it. I took it to a specialist and they told me the turbos needed sending off again for refurbishment which I wasn’t prepared to pay for.

Won’t be buying another bmw anytime soon.

Who did you use for the turbo reconditioning the first time it was done ?

[KoktGrus]

Anyone found a solution for this?
Thinking of removing my turbochargers for inspection, but when reading here that some people changed/refurbished their turbochargers without any difference it feels like a large job that might be unnecessary.

Thinking of removing my remap, but it seem to happen to stock engines as well?

[RRR77]

I have the same issue. Car pulls ok up to 3000rpm ish, after that it lacks a lot of power. Driving 535d gt from 2011, so its N57S - 299hp engine.

No fault codes. No issues whatsoevert apart from missing power

So far done:

-all vacuum lines
-both pneumatic converters
-cleaned intake
-cleaned intercooler
-removed small turbo, not issues
-removed dpf to be able to see wastegate and large turbo exhaust side
-checked large turbo intake side
-tested vacuum canisters
-checked turbine control flap physically, and with ista
-checked wastegate physically and with ista
-checked bypass flap physically and with ista
-checked egr
-did full i-level update, no remap before and not now either
-fuel pressure fine
-timing done, because of chain elongation. Now everyything is new.

Actual air mass and boost values are fine till 3k ish. After that there is significant difference to nominal value.

Any ideas? Vacuum pump runs full vacuum when engine is started.

The trouble seems to be worse when engine is hot.

Any ideas?

[mu6a4]

Someone please tell me you were able to find the cause and fix this....
I'm having the exact same issue and we tried everything possible with no success

[rasa bmw]

ive replied to mu6a4..my prob was to much fuel top end,so was requesting more air which it could not give,remap changed and prob went away,had car data logged on some runs etc,then sent to jason at bwchiptune,then the guy who was working on my car put a celtic tune on it,he had advised in the beginning aboutbremap etc,but i dismissed it,