I know I’ve talked about this,,,,but maybe someone hasn’t seen it yet,,,,besides this was my fun for the day,,,,N20 smoke during cold start up in the morning,,,,it’s a blue smoke,,,smells like burnt oil,,,,it will smoke for about 20 to 30 seconds and then go away,,,,the picture is the engine oil feed line to the turbo that causes the problem.
Here you can see the turbo,,,,and just left of the turbo is the engine oil feed line,,,,the oil line goes from the engine block to the turbo housing,,,,you have to remove the whole turbo to replace that oil feed line.
Here is the difference between the old and new oil feed line,,,,the new oil feed line has a built in check valve,,,,which stops oil from leaking into the turbo while the engine is off,,,,what would happen is oil would leak into the turbo over night and cause the blue smoke coming out of the exhaust during cold start morning,,,,that check valve in the oil line stops that.
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How much would a replacement like this cost out of warranty? I’m having quite a lot of blue smoke on startup with my 328. Thanks!
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The oil feed line is not always the fix,,,,,I’ve had several car with the turbo is the cause,,,,and when I replace the turbo I also replace the oil feed line,,,,I don’t know the cost,,,,we don’t see the cost of the repairs,,,,it does pay me 5 hours labor,,,,check where you live,,,,in California we have a emissions warranty that pays for the turbo up to 8 years up to 100k miles,,,maybe your state has something like that,,,,good luck
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Would something like this be covered by the 8yr/80k mile federal warranty? Thanks for all your help, I’d prefer not to replace the turbo as I know I’d probably be very costly. If its too expensive I might just let my car burn oil for a while.
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I might be covered under the federal warranty,,,,you would just have to check the federal warranty list on what is covered,,,,,in California it’s covered under the California emissions warranty for 8yr/100k
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Hi , would you know if the turbo on the e89 can be removed from inside the engine bay. I know on the 3 and 4 series 328 and 428 the steering rack is moved forward and done from below. There looks around 10 inches of room on the e89 to maneuver it from top. Also can the oil supply pipe be changed from the side on the e89? There seems plenty of room. My car is out of warranty, am in the UK so no extended warranty and it is blowing smoke on startup. Ive ordered the updated supply pipe so we shall see. A used turbo is another option if mine is gone. Can the seal be changed inside the leaking stage? Why does the BMW version of the reliable Mitsubishi turbo suffer from this? My car only has 30k miles. Many thanks.
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I have not replaced a turbo on a E89 yet,,,,but I can tell you I have replaced a turbo on a 3 series from the top and the bottom,,,,,the bottom was easier,,,,you have to remove the turbo to replace the oil line,,,,,you can not replace the turbo seal,,,,unless you find someone to rebuild your turbo,,,,,BMW has a contract with a different turbo company.,,,,maybe Mitsubishi couldn’t make what BMW wanted at the time,,,,who know what they do sometimes,,,,lol,,,,I hope this helps
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Many thanks for replying I only ordered the part 11428678840 the updated tube from 2016 with the check valve hopefully this will work for me on my z4 . I only looked at it last night and this morning I started it it ran for 1 minute and shut off struggled to restart it it idles at 400 rpm shaking badly and won’t rev past 1500. I only looked at it yesterday no work. Bad luck or what. I had to take my mothers car to work . No fault came up on the dash. I wonder is it fuel pump or something hopefully not the vanos unit? I feel like crying..
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Also I noted the turbo can be split by undoing the clamp to the manifold and water lines/oil lines and air intake away from the car. Do a search for dinan turbo upgrade n20 pdf and it gives a how to. I’m wondering if the oil line can be removed if I can get the front section of the turbo out leaving the manifold in place. Thanks.
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I don’t know if I would split the turbo housing,,,,if it doesn’t go back together correctly,,,,,then the turbo propeller shaft must turn freely,,,,,no binding,,,,,could cause you more heart ache,,,,my recommendation take the turbo off in one piece
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Thanks, do the fuel pumps give trouble on these, Im going to scan it this weekend but is this likely. It idled poorly wouldnt rev over 1500 revs and then wouldn’t restart. No oil pressure light or fault light even though it was idling for 1 minute poorly. The timing chain seems ok visually through the oil cap. No timing chain noise was apparent before, the miles are around 34000 its a manufactured mid 2012 Z4 28i. I will scan it this weekend with Inpa .Thanks
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No we really don’t have to many problems with the fuel pump,,,,we do have some problems with the fuel injectors,,,,remove the spark plugs and see if they are fuel soaked
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Will do this weekend and will report back Im praying its not the chain (and I think it isn’t as no low oil pressure if its the oil pump chain, and no noise before I listened carefully 500 miles ago) many thanks
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Hiya , I removed and checked all 4 plugs after trying to restart it which it tries to kick and sometimes even runs for 20 seconds. The plug ends are all blackx4 but all are wet which evaporates so I guess must be fuelm and you can smell fuel. Do you think one injector has failed dumping fuel in, if so why don’t the other 3 cylinders run the car and which one is it likely to be ? Can I disconnect injectors one cylinder at a time?
A fault code did come up and I scanned it and it was loss of power Im not sure of the fault number. Many thanks again.
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You might have more then one injector bad,,,,,yes you can unplug one injector at a time and see if it runs
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Ive tried unplugging the injectors one at a time still leaving all coilpacks and the turbo vacuum connected and it still does not start. I seem to have a diagnostics version V57 that doesn’t have the 28i version but perhaps dates previous to this with an option of e89 23i 30i and 35i. If I had the latest diagnostics version would this likely tell me what is wrong as I will pay a mobile diagnostics person to test it. I have a 2002 audi tt which failed to start once and it was the and the crank position sensor and a code came up from crank sensor and a 2008 passat tdiThe fuel pump in the tank gave no code and I replaced it on a hunch as a common fault and it was fine.
What would the chances of two injectors failing at one time? Must be long odds.
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It’s very possible ,,,,I have seen 3 injector fail at the same time,,,,how many of the spark plugs were fuel soaked.
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Hiya , I fitted new bmw ngk plugs after drying out the engine by cranking it and using compressed air through the plug holes but they quickly drowned in oil but it did fire and run a few seconds. Fuel spurts from the fuel rail when the nut is opened so fuel is getting in ok. All four cylinders are equal and no excess smell of fuel just oil on the plugs fouling them. I think the more time it sits the more turbo oil that gets in. An update though after a day of dissapointment. The pipe that attaches to is it a filter on the engine cover seems to go to the area under the fuel rail on the head there is vacuum on when released I released it and a hand full of engine oil came out of from the engine side. What is that pipe for and us that turbo oil coming out? Does the engine need to be started with that pipe connected? Many thanks again for help thanks
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Ok,,,,the line your taking about,,,,I’m having a hard time figuring out what line your talking about,,,,I think the line you are talking about ones to the vacuum pump which is at the rear of the valve cover,,,try and trace where it goes,,,,,ok if that line goes to the vacuum pump,,,,yes you can run the engine with that line off,,,,,check that line and see if there is oil inside,,,,also check the vacuum line to the waste gate,,,,,,see if there is oil inside any vacuum line,,,,,if there is oil then the vacuum pump is bad and is pumping oil inside the valve cover and vacuum lines.,,,,that could be your whole problem.,,,,,,I think I have something in my blog about this.
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I thought of something,,,,did the plastic engine cover,,,which might have 1 or 2 vacuum ports on it,,,,does that have oil in it.
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An update.
Fuel pressure check(took line to fail rail off and squirted out under pressure, reattached and tried to start took line off fuel squirted under high pressure
Spark (one one cylinder)check-removed plug and attached to coil and grounded to chassis and smoke coming off as it burn the oil off
Injectors check, no spark plug is excessively wet , no big smell of fuel from exhaust but some light smell of gas, disconnected one at a time made no difference
Crank position sensor check a reading coming off this
Cam postion sensor unknown no reading available
Maf sensor unknown no reading
Injected starter spray into spark plug hole with known working coil and turned over engine and did not even kick
Compression test to check timing chain/valves unknown will do tomorrow
No fault codes registering other than injectors but only after unplugging them one at a time
Throttle body- and this is the interesting part- flap not operating on pressing accelerator seems fully closed no air getting in, oil present inside, it seems that the defective oil line likley sprayed oil into the throttle body and the car acted funny and then died when it was idling with smoke pouring from the exhaust if I have my plumbing correct of the turbo oil seal failure and the oil is ending up in the throttle body. Will test tomorrow, interesting.
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Yes this is very interesting ,,,,,was the engine running before you did turbo oil line,,,,,and after replacing it now it won’t start?
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I never touched it, I bought the oil line ready to install, and before I could touch the car, I let it idle smoke was coming out of the exhaust on startup then it died, I restarted it ran roughly wouldn’t rev above 1500 and then die, restarted would kick run for aa few seconds, now wont run at all. So in summary nothing was done to it not even a cover lifted. Just bad luck I suppose, Im going to compression test it this morning and wedge the throttle flap open to see if it starts on starting fluid.
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Ok,,,,I understand now,,,,you said you smell fuel and spark plugs were black,,,,you could have a couple fuel injector that are bad,,,,that would cause it to run bad and stall while idling ,,,,we have had some cars towed in because they can run with bad fuel injectors,,,,if you find spark plugs fuel soaked,,,,then those injectors are bad,,,,and could be your problem,,,,the spark plugs should not be fuel soaked.
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Hiya, checked compression and that is fine same in all cylinders. The spark plugs are indeed fouling black but in all the cylinders I think, I took one out got no spark only smoke on the plug tip when the engine cranked then cleaned it and you could see the spark. Could all 4 injectors be bad or Is it not more likely to be the turbo oil in all the cylinders, after all it quit while idling with the smoke coming out of exhaust when left overnight?Also isn’t petrol usually not black? Very strange.
Il order 4 plugs tomorrow and fit them and retry.Thanks
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Yes replace all 4 spark plugs,,,,if you can blow out the spark plugs hole try and get all the old oil and fuel inside the cylinders,,,,so you will have a clean spark during start up,,,,good luck
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I will try cranking the engine with no spark plug to blow out the oil /fuel. Thanks
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Hi ,that’s a good question whether there is oil in engine cover,Il just check, Im not sure.
Ok just checked and although it was left overnight no there is not, I took off the pipe from the wastegate to manifold and there is no oil in this either. But the pipe from the engines vacuum pump to the engine cover was full of oil with a lot of suction . Would/could that be linked to a non start situation?What does it mean if this is full of oil?
I noted in the manual that if a certain symbol appears then car can only be started with the foot brake depressed I am going to try that as I nearly had it going last weekend.. Failing that it will be towed to my garage likely with more questions than answers.
Oh one other question how do you reset the electronics , I have INPA Dis v57 and it doesn’t have the 28i but the previous model the e89 23i, can the electronics be reset with this?
Many thanks once more
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On the dis,,,,,no you can’t reset the software is not up to date for a N20 engine,,,,,if there is oil in the vacuum pump line,,,,then the oil pump is bad.
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Hi I kind of figured that it was but for the moment getting it running is the main thing I don’t think the vacuum pump is the problem. It is just cam driven oil lubricated so if no oil is getting into the vacuum lines no damage is done yet. I’ll update the thread once its running. My money is on the injectors , likely the turbo oil damaged them all equally. It ran on limp for 2 minutes likely one or two injectors died then in limp the other two died. We shall see😊
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Sounds good,,,let me know what happens
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Your vacuum pump non return valve is worn out and allowing engine oil to go to the vacuum reservoir and waste gate actuator. It supposed to allow suction only and prevent engine oil pressure surging to the waste gate actuator. I replaced mine,
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Thanks for the video
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I think the vacuum pump is a red herring. I belive the issue is the 4 injector are clogged by oil deposits, the same that clogged the first set of plugs on startup. That my hunch anyway
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Will do
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Im still having some trouble with the car. I sent it to my mechanic who says its coming up with a valvetronic fault code. Is there anything in the valvetronic that would cause it not to start?
Thanks
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Yes the valvetronic motor and can cause it not to start
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Hi, update is that he has scanned car and its coming up with2DCF-valvetronic system no movement detected In trying to do valvetronic learning procedure it fails. He says the valves are not moving or moving properly. This would likely explain the 50 max compression I got in all 4 cylinders when I compression tested it which would be low. He has changed stepper motors before but not on N20s. He has logged into BMWs website and says there is no readings on what volts should get on connections prior to considering part replacement. It could be the fuse, relay , wiring harness, stepper motor or possibly the ecu I suppose. If you could shed any light on fault finding would be great. The car has been towed 40 miles from me so I wish to get it back on the road. Thanks in advance
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Ok I looked at the wiring diagram,,,,looks like there are no fuses and no relays,,,,valvetronic gets its power and ground from the DME,,,,terminal 5,6,7 and 11 on the plug connector that plugs into the valvetronic should have power,,,,don’t know the voltage could be 5v to 12v,,,,terminal 10 is ground from the DME,,,,,hope this helps
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Thanks Il let him know, considering there is no fuses or relays and the wiring is unlikely to be defective as it died in the driveway idling ( although I supposebit could be fatigue failure of wires from the vibrating running engine)would you recommend just replacing the motor which has the sensor in it I believe? Is there a replacement procedure for it on bmw tech site? I was also thinking of purchasing the Bentley publishers 3 series manual with n20 engine as they tend to go into very detailed information but there is the time to order from the States as I’m in Ireland, many thanks Gaurav
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Yes you can replace it,,,,I don’t know what information the BMW tech has,,,,the Bentley book might be good if they cover that repair.
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Many thanks again Il update when sorted
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Sounds good
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Hiya, I got the Bentley manual,BMW N20 manual from the X3 , and Mitchells wiring diagrams. There is a relay and fuse that supply the DME dedicated to the Valvetronic not on the wiring diagram. Its relay k6316 in the left of the engine compartment. Also a 40 A fuse next to it. So I will go down tomorrow to the garage and check these, the volts on the Servomotor, check loom continuity and finally can I ask is it safe to turn the valvetronic servo motor 3 times with a 4mm allen wrench to reset it . I got that advice from BMW mini manual for code 2dcf this is due to the motor being at an end stop and turning it 3 times presumably takes it away from that and allows it to relearn the positions. Is the allen turned clock or anti clock? If all this fails Il get the servomotor replaced per the repair manual. It specifies tool 117170 and PD1 lithium grease. The tool 117170 I think is to lock the eccentric shaft. Does this look like an allen key or some kind of grabber for the shaft? Many thanks once again. Hopefully she will be running soon and Il have the turbo oil supply pipe replaced!Cheers
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I don’t remember which way you have to turn it,,,,but you can only turn it one way,,,,,the tool is to help turn the essential shaft and hold it in place,
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Hi, many thanks, we will probably be able to rig a tool up to hold the shaft, I think there is a flat on the end that can be turned by a wrench looking at the repair instructions. Pray for me and my baby!Il let you know thx
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Ok,,,good luck
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Sorry for not updating sooner. It was a valvetronic motor failure which also took out the dme. The dmes are very poorly positioned it seems on modern bmws , the n20 directly behind the oil cooler meaning the in use temperatures are over 70 degrees c, burning hot to touch. I put two reflective heat shields in one behind oil cooler and one to left of dme reflecting heat away from engine side. The dme is only luke warm now in use but does get hot when the engine is switched off from heat soak but still not for as long as in use. I also removed a small section of insultion over the valveteronic motor to lower its temperature.. Wrt turbo there is too much labour with fittimg an oil line and seeing if it works. The cause is a worn seal likley from poor engineering the oil line is just a patch. I had my turbo rebuilt and the oil line fitted.Im hoping the updated oil line doesnt kill the turbo as it isnt a one way valve but a pressure valve afaik. So it might reduce the oil available to the turbo. Well see anyway…
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The new oil line does not reduce the flow of oil,,,,it just stops the flow when the engine is off,,,,so the turbo doesn’t get all this oil when off and then you get this oil burn off during cold start.
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That may be true but looking at realoem as far as I remember bmw still fita the standard non pressure valve to new bmws. Obviosly if that is the case the engineers are unhappy long term with this patch that is likly tobsee the turbo out of warranty. My turbo was rebuild at 37000 miles and the reputable guy doing it says it was shot and in a bad way. What the reality is I cannot say as wasnt there and dont have the direct technical knowledge but I know that any manufacturer that mounts the dme behind the oil cooler employs very poor designers. They do have first class styling and interiors as well as brand name so I guess that keeps them moving off the lots.
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I do agree it is pretty strange that the DME is mounted on top of the intake manifold.
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I believe the six cylinder versions the dme is mounted with the base inside the air intake but the top max be behind the oil cooler too. TheM5 I believe is liquid cooled and has water in and out ports!. Why not just place it in the under wiper tray with some good drains or beaide the brake reservoir which is behind a heat shield? Weird…
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Yes BMW has different places for there DME ,,,they use to always have them in a special DME box but not any more
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Sorry for poor spelling I am on a little android phone!
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It ok,,,I understand
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Had the wastegate actuator linkage break on my 320i N20 engine. Does the wastegate fail in the open or close position? In your experience what damage can you expect from this kind of failure?
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I have never seen the linkage break,,,,I would make sure the arm on the turbo is not damaged or binding in any way
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hello with the bmw. n20 mileage 55,000 miles in the morning I start the smoke with the back of the otom all day long nedymit tell me what to body beforehand thank you
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If your car smokes in the morning when you start it then you should replace the turbo oil feed line with the new updated oil line which will stop that problem
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I commented on your comment and ordered the feed hose for a little new version of the original code 1142 8 626652 but it went without a valve like you in the photo, maybe I did not order it correctly if not, then you can help give the correct code. thank you in advanc
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That part number is the original non check valve oil line,,,,you need 11 42 8 678 840 with check valve,,,,,any BMW should have the part in stock,,,,tell them the new update oil line with check valve
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thanks for the help
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Hi there, I’m looking at buying a BMW X1 2013 with an N20 engine. I’ve had the car inspected and he has found that the turbo is leaking oil, and dripping down onto the steering rack. Would you be able to let me know if this is more of a repair than just changing the oil feed line? If the turbo itself is leaking out, does that mean it is likely that the whole turbo needs to be replaced?
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Yes you have to replace the whole turbo which is not going to be cheap
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So I’ve got more information about where the leak is coming from. It looks to be the plastic hose the is connected to the intake of the turbo. I’m not an expert in this but this is the photo (https://imgur.com/a/doEm5SN). I would hugely appreciate it if you could confirm that is the intake end of the turbo!
If it is in fact the inlet of the turbo I’ve read (from Bimmer forums) that is a matter of replacing the gasket there. Apparently according to the forum the N20 is not great at handling the oil blow-by from the PCV. Again, I’m just repeating what I’ve read, I’m no expert 🙂
Any advice would be much appreciated!
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Hello man
I have a 328i n20 engine i changed the oil feed line to the updated one with the check valve
When we were changing it we found oil in the intake system
Btw i changed it today and dont know if the smoke on cold start has gone
Whats does it mean oil in the intake ?? Bad turbos ??
I only see smoke on cold start for about 15 sec and when it sits more and more there is more smoke So no smoke after the cold start
Thanks for helping
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The oil in the intake should be from the oil line,,,,after you replaced it does it still smoke?
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I changed it today i will wait two days before starting the car and check if theres smoke
But the intake is from the compressor side not the exhaust side
There was oil in the intake tubes i cleaned them and installed the new oil feed line with the check valve
Is it a symptom of a bad turbo ??
I will check the smoke after two days and let u know m
Thank u man for helping us out!!!
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That’s normal to have some oil inside the intake tube ,,,,should be fine after the turbo oil line update repairs.
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Okay man thank u so much !!!
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Started the car today and no smoke at all
Hope I didn’t damaged the turbo !
Anyways thanks alot for ur help!!
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That’s good news,,,,and no you didn’t damage the turbo
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Hello sir how are you hope ur doing well!!
Hopefully no smoke at all after the turbo oil feed line replacement
But after changing it and removing the turbo to install it
After the replacement theres a small sound of whistle/ whine sound when acceleration on low rpm as soon as i release my foot on the acceleration pedal the sound goes out
We maid a boost leak test using a machine that spays smoke and there is no leaks al all
I found a video on youtube this guy has the same exact sound
Hope u can help me
Thank u !!!!!
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Thanks for the video,,,it hard to say what that whine whistle noise is,,,could be the turbo whistle,,,,does it happen only during boost?
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Yes it only happens when accelerating and as soon as i release the power on the acceleration the sound goes away
After 3000 rpm theres no noise
It only happens on low boost you can here the turbine of the turbo
This problem occurred after the turbo removal for the turbo oil feed line
What could be the problem?
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Ok,,,and you said you can find any intake leaks,,,what about any exhaust leaks?,,,,question did the turbo propeller look ok when you removed the turbo.
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We checked for exhaust leak and all was okay no leaks
The guy said when he removed the turbo the turbine was good there was a little of play and he said its normal and he have checked alot of n20 turbos
Can the turbo turbine be unbalanced ??
I dont know this problem is driving me crazy
Thanks anyway
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Yes that is normal a little play in the shaft,,,,could the turbo turbine be unbalanced maybe,,,but you said it happen right after the repairs so I’m wondering if it’s something the technician did,,,because nothing changes with the turbo after replacing that oil feed line,,,I wish I could hear the noise in person to help you better.
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Sorry its the wrong name its jean
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