[AshleyB_UK]

Hi guys,

I've noticed a few times recently, particularly in hot weather, that the turbo on my 2006 E90 doesn't kick in at the usual 1300-1500ish RPM. It seems to lag right up into around 2k or 2500k.

It has done it a few times and is very noticeable, as mentioned, particularly when the weather is hot (25+C) or when the car has been stood idle with the engine running for an extended period of time.

Is this some ECU trickery to try and keep the engine temperature down during periods of excessive high temperature or is the turbo on it's way out?



I have tried killing the engine and restarting it which does help a bit. Strange one though.

Has anyone else had any experience of this?

Cheers,
A

[basim07]

I've got the same engine as yours and mine doesn't kick in till 2-2.5k as standard!

You can hear it spooling from about 1.5-2k

You sure it normally kicks in at 1500 on yours?

[KM79]

Engine possibly needing a decoke.the valves get gunked up with carbon and restricts air flow into cylinders.

[makkan00]

Originally Posted by K_M79

Engine possibly needing a decoke.the valves get gunked up with carbon and restricts air flow into cylinders.

And how do you do that mate?

[KM79]

Mak,a proper decoke on an m47 is cylinder head off and manual clean to scrub all the carbon off.But...the last one we did we managed to get decent results with the walnut blaster and a homemade adapter!

Kris

[old grey steve]

Internally they do get coked up as K_M79 says there is a walnut blasting procedure for the diesels oddly enough as well as the petrols but its more involved. To give you some idea over in the states(though this isn't a 320d there an SIB on it as this E90 post thread reveals http://www.e90post.com/forums/showthread.php?t=983574 they do coke up quality of diesel etc may/isdifferent over there but matter not its still an issue! You can do the old fashioned decoke the BMW route is head off=money but the above post proves diesle and walnut blasting go together but the adapters are slightly different

Out of interst is the car one of the N47 engines (later spec) or one of the M47N2's? I'll assume that its the M47N2 unit but I could be wrong.

Me judging by the comments I'd stick my neck out and look at the following which hopefully a half decent garage would check via diagnosticand by some good old fashioned detective work

Firstly I'd look at the Turbo wastegate which is electrically controlled, quick check would be to see if the actuator is operating as it should if its lazy/stuttering as this if its the case could be an issue. I've tried my best to circle what/where unit is but you can see when checking via diagnostic the road "juddering" if you can call it that and then suddenly it'll spring into life



Secondly I'd have a look at the electric valve (labelled as No11 on this attatchment which is for the M47N2

http://bmwfans.info/parts-catalog/E9...lap_control_2/

we've done a shed load of them and they "seem to break down so to speak" once replaced car goes like stink.. question is after they are repalced did the unit fail suddenly or did it over a period of time lose its efficiency? Whatever the case when these are replaced transforms the car. Cars reported as lazy lacking energy then suddenly it'll pick up.

Small chance we have a pressure convertor fault (labelled No1) not unheard of

http://bmwfans.info/parts-catalog/E9...m_control_agr/

Thing is at the end of the day you can have wild stabs all day on here based on the OP's(no offense)description its best to get the car to a decent Indy who's got a)AutoLogic diagnostic equipment or something of similar spec & b)a brain

You've got vacumm pipes and god knows what else to look at/rule out. But keep us in the loop re the outcome but the mere fact that you say 2000/2500rpm then it springs to life means I'd be looking at the 3 things indicated not really the coking aspect as the fact that its all choked up is a diesel trait I'm afraid the heat tells me its one of the things described above perhaps who knows a heat soak breaking down type fault

[KM79]

Turbo could definately be on the cards as Steve has said,and a 2006 car would have the m47 engine.Strangely though most of the coked up ones I see are x3's even thigh the engine is the same as e9x.Maybe driving profile is different for the two types of vehicle.if you have choked internals they're will be a 'mass airflow plausibility' error code so worth getting a diagnostic session done first.

[AshleyB_UK]

Thanks for the great feedback guys.

I am aware of possible swirl flap issues with BMW Diesel engines. I'm quite sure this isn't an issue on this model of engine though (According to Haynes it the M47 engine).

That car is 8 years old but has only done 53k.

The turbo definitely takes effect around 1500rpm. As mentioned, it's not a major issue, the car performs perfectly 98% of the time.
Looking back at it's history, it has had years were it has done less then 3k miles wise so most probably stop-start style town driving which may have contributed to the build up of shite in the engine. I have had it 3 months and have already put 4k on it with long motorway drives and town driving combined.

If I were to de-coke it I would probably get the inlet manifold off and give the swirl flaps a clean as well as checking the screws are nice and tight. Mechanical stuff I 'm happy to do, electronic stuff...not so much.

If the problem persists and worsens, I will end up booking it in at a specialist I think. Get it sorted properly.

Cheers all,
A

[ptpending]

you need to perform diagnostics, read engine live data and compare with "should-be" parameters

[old grey steve]

Originally Posted by AshleyB_UK

Thanks for the great feedback guys.

I am aware of possible swirl flap issues with BMW Diesel engines. I'm quite sure this isn't an issue on this model of engine though (According to Haynes it the M47 engine).

That car is 8 years old but has only done 53k.

The turbo definitely takes effect around 1500rpm. As mentioned, it's not a major issue, the car performs perfectly 98% of the time.
Looking back at it's history, it has had years were it has done less then 3k miles wise so most probably stop-start style town driving which may have contributed to the build up of shite in the engine. I have had it 3 months and have already put 4k on it with long motorway drives and town driving combined.

If I were to de-coke it I would probably get the inlet manifold off and give the swirl flaps a clean as well as checking the screws are nice and tight. Mechanical stuff I 'm happy to do, electronic stuff...not so much.

If the problem persists and worsens, I will end up booking it in at a specialist I think. Get it sorted properly.

Cheers all,
A

Understand what you are saying and cleaning everything out may/will help matters thing is look on this forum and others and no matter how its described there are issues going on elsewhere effecting the cars running hence the post I put up to help you, you really need the car looked at by someone who understands why these things happen TBH that what I'd do as you need to know what's going on what's wrong and for me more importantly why the faults actually gone wrong, the SnapOn equipped garage that'll do something for £30 will struggle decent indy's your best option.

I'm looking at an X5 right now been to 3 different garages all diagnosed different things turns out the electric valve(sits under and by the inlet manifold) I've mentioned was at fault. Replaced goes like stink. It took us 15 minutes to look at the data and understand what the hell was going on... knowledge is key but then so is basic understanding. Any indy with knowledge will follow the same route

[Pumper]

Mine does not perform as it should as well - I floor it and have to wait a few seconds for the turbo to kick in.

Before replacing MAF sensor I got a 46D3 fault code (Internal Control Unit 4) along with several MAF related ones. Replaced MAF, cleared the fault codes, checked again and 46D3 was the only one that came up again.

Looked it up once more today, after reading this thread, and found a Slovakian forum where the guys are talking about the same fault code with similar performance issues and they figured out that the turbo's vacuum hose was broken.

Any ideas which vacuum hose this might be?

BTW, fixed a leak on intercooler a week ago - did not help with performance issues.

[old grey steve]

Originally Posted by Pumper

Mine does not perform as it should as well - I floor it and have to wait a few seconds for the turbo to kick in.

Before replacing MAF sensor I got a 46D3 fault code (Internal Control Unit 4) along with several MAF related ones. Replaced MAF, cleared the fault codes, checked again and 46D3 was the only one that came up again.

Looked it up once more today, after reading this thread, and found a Slovakian forum where the guys are talking about the same fault code with similar performance issues and they figured out that the turbo's vacuum hose was broken.

Any ideas which vacuum hose this might be?

BTW, fixed a leak on intercooler a week ago - did not help with performance issues.

As I said above thee are many reasons why these things come about just because you see a code don't automatically assume it's X or Y vacuum hoses sure play up fray/collapse and create grief at the same time these hoses are connected to various components again these need checking and as I've said we do see a shed load of pressure converters and the electric valves are labelled above in my post and these are all connected to........... vacuum hoses

So worth checking the obvious but don't discount the other stuff

[kukjan]

have a power loss...

[u2b]https://www.youtube.com/watch?v=3X8t998NQ2E[/u2b]

think problem is in number 1, but i can find this F*ck*ng sh*t!
m47n2 e90 07"

[dy63]

didnt think the turbos kicked in before 1500 rpm?? im sure every BM ive drove its kicked in around 1800-2500

[Digitalize]

My M47N2 you feel it start to affect engine power around 1700, by 2000 you can put your foot to the floor and it will pull smoothly.

[kukjan]

Check my video.. And you will see my problem

[kukjan]

Oh, it's not vacuum , it electronic...
Any ideas??

[OGM2LCI]

Mine did this a little during the winter months, would be lumpy on start up and then major hesistation for the turbo, to explain it better...I would press on the accelerator a 'normal amount' and the revs would slowly rise and there would be nearly no acceleration until anywhere between 2000-2500rpm when it would shoot off? However it was inconsistent, if it idled fine then I could guarantee this lagging effect wouldn't happen...is this the same as what you're getting Ashley?

Edit; 03/2008 320d N47 engine

[Jase 320d]

Originally Posted by kukjan

have a power loss...

[u2b]https://www.youtube.com/watch?v=3X8t998NQ2E[/u2b]

think problem is in number 1, but i can find this F*ck*ng sh*t!
m47n2 e90 07"

Number 1 looks like an n75 valve to me (charge pressure solenoid)

[kukjan]

Originally Posted by Jase 320d

Number 1 looks like an n75 valve to me (charge pressure solenoid)

Yes, it is, but people's told e90 don't have it, there is turbocharger Mitsubishi and there electrical valve, not vacuum... So if problem with it, need replace turbo... ;( but on Russian forum founded same problem,
And one guy try to clean part number 11

And car started pull, but not for a long time. So he wrote will replaces this sensor, and no more answer from him...
Will try to clean it today...

[Jase 320d]

Thats the map sensor

If thats the issue just buy a new one not that expensive

[kukjan]

Originally Posted by Jase 320d

Thats the map sensor

If thats the issue just buy a new one not that expensive

I hope this is map lol