Bmw valvetronic,Explained,Diagnosed,Fixed

[@skrevox]

Aaaaah the lovely N46 engine. Between the endless valvetronic faults, valve stem seals made of cardboard, timing chain guides also made of cardboard and the endless oil and coolant leaks, there is never a dull moment with this one.

[@Diagnosedan]

At least there is always work to do😅

[@ademc8872]

Mechanics gotta eat too😆

[@Diagnosedan]

@@ademc8872 🤣🤣

[@kevinbarry71]

German engineering; job security for everyone.

[@Diagnosedan]

@@kevinbarry71 🤣🤣

[@hightower001]

İ have never seen someone explained this much good information about valvetronic and why there is still throttle valve, thanks 👌

[@htownblue11]

YES! I did this job once and can’t wait to hear DD break it down. Already smashing the like button. Diagnose Dan never disappoints.

[@Diagnosedan]

Thanks!

[@stevenfurayi8607]

@@Diagnosedan Hi Dan I have got the same car and I have changed the valvetronic motor and done the limit learn and it will work for a few days then through an engine check light. Recently it through a check light for the exhaust cam sensor and I replaced it with a new one but still notthing changed.

[@karelrysavy334]

@@stevenfurayi8607 check the connectors to the 2 vanos solenoids, check and clean those solenoids using a toothbrush and brake clean (or similar), reinstall, reconnect properly and see whether it solves Your problem.

[@pantelis241]

Dan you are awesome 👍

[@dhalsim-1]

I've been looking everywhere for a good video that properly explains valvetronic motor issues, and now I've found one. Cheers

[@ZetMuzic]

Wonderful job as always. Once I opened a motor for my curiosity and I've found a lot of brush dust inside. I disassembled and cleaned all inside, changed brushes with a new pair and assembled back. Resistance to ground disappeared! This experiment leads me to believe that the dust inside accumulated and started to conduct electricity and short to body (ground). Resistance should be infinite to body (OL) since brushed have no contact to body.

[@pokkeljaan]

How do you open it?

[@ZetMuzic]

@@pokkeljaan With an "L" Blade on bench vise and workaround with a small hammer where is closed

[@dgeneralmusiq]

@@pokkeljaan kzbin.info/www/bejne/o2fWf6png6-YgLs&ab_channel=EnduroShot

[@DearMajesty]

great comment, thanks man!

[@soundseeker63]

Thats a very logical explanation and a very smart and economic fix. New motors from BMW are painfully expensive! Where did you source the brushes from, and how did you open up the motor? Thats a worthwhile tutorial video in its self!

[@thatinsaneshift]

You are a life saver, Had been stuck with rough idle, new spark plugs going black because the car wasn’t being able to burn fuel and a crank code. We were on the verge of opening the engine on my E90 325i until I came across this video. Now, My car is fixed and ready to make some white smoke again! ❤️

[@pierrejordaan3301]

Thank you Dan, it's been waaayyyyy to long since your last video. Always looking forward to learning from you.

[@Diagnosedan]

You are right Pierre it's been to long!

[@binbetrand4210]

@@Diagnosedan thank you for this video I have the same problem

[@carlosmaurencig6763]

The case test is absolutly definitive to condemn the motor, for the windings i prefer the load test with a high amperage bulb Great video, Danny!

[@Diagnosedan]

Thanks for the feedback Carlos

[@kevinmartin9432]

Outstanding video, it's easy for us "older mechanics" to get intimidated by "new stuff", but you explain it so well, thank you😎

[@maximillian6184]

Let me say, this was the best diagnostics video I've seen - Well done, Dan!

[@ncux555]

Я очень плохо знаю английский язык, но в этих видео всё понятно! Многому учусь от тебя, Dan. Привет из России!

[@MuneebMehmood-s4r]

dude just literally took the cover off and showed a live demonstration of how the valvetronic system works. loved it breh keep up the gud work

[@MrFryfish]

Clever, clever, clever; very well explained! Thank you Dan! And yes low resistance to the body or case of any electric motor it is a bad sign that that motor is about to fail, if not already faulty. The isolation resistance between windings and the case should be at least 1 Mega Ohms, if not more; tens of Mega Ohms.

[@Diagnosedan]

Thanks for watching

[@dans_Learning_Curve]

Oh, I just put two and two together! MEGER (Testing device) Mega OHM

[@MrFryfish]

@@dans_Learning_Curve that's right; forgot to mention; that Megger it is an expensive tool, that sends a preset high-voltage in pulses down two wire or mediums with the intention of testing exactly that - isolation resistance between wires.. Well, it is good enough to just get no resistance between case an windings or between 2 different winding to get a high reading.. and that will, kind of eliminate a potential issue. But as Dan is saying, with temperature, yeap, the insolation/wire will expannd and the isolation can change do to temperature.. A tester as the one above, it is good by using it to zapp higher voltage and physicaly destroy the isolation and make worse the isolation and conclude that probably that isolation was prone to fail. BUT that test should be done with caution because too high voltage is detrimental and has an irreversible effect!! Just a word of caution when using a higher specialized tool. A multimeter will measure the resistance by sending much, much lower current down the wires and verify the resistance of the medium..

[@deathmaniac95]

@@dans_Learning_Curve Yeees! a insulation resistance tester o meger must be used to evaluate the condition of insulation of a motor, but if the fluke handheld tester measures something, you are screwed haha

[@deathmaniac95]

@@MrFryfish exactly! beautiful explanation dude!

[@trevormansfield6740]

Brilliant video. You are without question the best diagnostician on KZbin. Too many people over complicate things. Thanks.

[@Diagnosedan]

Thanks Trevor!😁

[@dubsydubs5234]

As always pin point diagnosis not changing all sorts of parts guessing, I worked as a auto technician for 40+ years and would have really enjoyed working with you, I hate guess it merchants, you always do it right in my opinion. 👍 I was one that commented on the capacitor on those fans, I just knew there was more to it than a fan issue, thanks for updating us it makes me happy to know my brain still works.

[@Diagnosedan]

🤣🤣 Well i listened to you, i hope your brain is satisfied 🤣 Even in the original Lexus Tsb they don't tell you what's wrong with the fan, so we went the extra mile😁

[@dubsydubs5234]

@@Diagnosedan 👍😁

[@dhrida5518]

The diagnose with the multimeter on the old motor could be considered, but it might not be accurate, unless it's a weak spot prone to fail, but it can be considered in following fixes based on the same system, great content! Also very educative and detailed on how these systems work!

[@nicknicu1787]

You’ve just destroyed another myth calling these engines “ over-complicated “. In my eyes this engine is way less complicated than a V-tec engine for example… As always,you’ve done a great job breaking it down so that everyone understands! 👌

[@Diagnosedan]

These engines are really not complicated (if you know what you are doing)😁

[@paulrobinson3528]

No way.............you can give me a Honda V-tec any day of the week and twice on a Sunday lol but they rarely go wrong, only the the little gauze filter gets clogged or wrong grade of oil, easy fix.

[@nicknicu1787]

@@paulrobinson3528 I wasn’t talking about reliability,but about the simplicity in design. The V-TEC is using solenoids and oil pressure to lock the camshaft on a longer duration lobe,while this engine has a simple extra camshaft driven by a worm gear motor.

[@paulrobinson3528]

@@nicknicu1787 It doesn't matter about how simple or complicated a design is in cars, its all about reliability, bmw's valvetronic and vanos systems are not reliable, hence why Dan is doing this video but i see what your saying.

[@mkaestn]

Got to scream the V-tec to get it to go! Valvetronic allows max torque to come in at 2800 rpm, on the n52 BMW instead at 4500 rpm like a m52 or m54 six just to make them go.

[@aktanf]

Another great video Dan. Just remember, before removing the Valvetronic motor, one must relieve the tension on the return spring by either putting the Valvetronic in the “service” mode, or by manually relieving the tension with an Allen wrench through the little pin hole on the back of the Valvetronic motor unit.

[@Diagnosedan]

I've done hundreds, always like this and never had a problem😁

[@2secondslater]

The tension on the valvetronic cam gets relieved when you remove the valvetronic motor, the valvetronic cam can be moved by hand after the motor has been removed

[@TheDonz]

I got a 320i 2005 and the valvetronic motor had no place on the back for a Allen wrench, even on the one that was replaced

[@gutsngorrrr]

Great to see another video, always a treat, showing what a real skilled tech is capable of where others have failed.

[@Diagnosedan]

Thanks Mark

[@KR33PATV]

This video helped so much. My son bought a 2011 328i xdrive which was in limp mode. Replaced vvt’s and it was still doing it. Bored a buddies scanner and it had low voltage bank 1 vvt. Watched this video and viola the vvt wire in trunk wasn’t plugged in. I know the guy he bought it from would be mad if we told him this

[@jasoneyes01]

Nice one Dan. I see alot of desinigrated ground straps on old BMW's. When these straps lose their capacity to flow current, bad things happen. The current tries to find an alternate path with up to 220 amps of arcing power. Electric motors get hot, arcing thru the driveline bearings... These ground straps are usually barried deep in the engine bay out of sight.

[@Diagnosedan]

Thanks for the feedback

[@99andrianmonk]

Dan - another great video. You take the complicated and make it seem like it's nothing so the rest of us can understand. You are truly an expert and superb instructor. Bedankt.

[@Diagnosedan]

Wow thank you very much, your comment is really appriciated

[@enda320]

For those with other Valvetronic issues, wear in the eccentric shaft is common, but also the valvetronic position sensor can crack internally and leak oil into the connector. This would be the electrical plug you see by the oil filler cap.

[@Diagnosedan]

You are right! Thanks for sharing

[@danielarevalo3525]

Would this cause smoke to come up everytime the car starts up and the smoke doesn’t smell like oil more or so like plastic ?

[@enda320]

@@danielarevalo3525 I don't think so. If the smoke is very quick, it could be a belt slipping. Oil smoke can be common if the valve cover gasket is leaking, some oil will drip onto the exhaust manifold, and after 2-3 minutes when the manifold is hot enough, it will burn off the oil and then you usually won't see anything again until the next day where more oil drips over night. The starter motor could have problems can cause electrical smoking on start up, but there's nothing particularly common to immediately start changing parts. Best option is to watch when someone else starts the car, and see if you can track down the location.

[@danielarevalo3525]

@@enda320 yeah im getting cylinder 3,5,6 and random misfire prob just the the coils or spark plugs, it only has smoke coming up when i turn the car on. The idle is deff like the video though

[@deaneybwoy4332]

@@enda320 I’m getting this exact same fault code in my 2008 bmw 320i however it’s also missing engine makes strange noise when accelerating and starting sometimes and moving sluggish can a bad valvetronic motor cause these symptoms?

[@arafat5710]

Respect from sweden. My buddies at the shop keep talking about you daily.

[@TheKeenMechanic]

DAN you are the most amazing Mechanic in the world. The effort and dedication is on a different level. You even sent the fans to be diagnosed and tested so you can let us all know and obviously satisfy your curiosity too. I wish you had more time to create more content for us. You are my idol and I hope that some day I am half as good mechanic as you are🤝

[@Diagnosedan]

Thanks! That's appriciated. Nice BMW collection you've got!!

[@TheKeenMechanic]

@@Diagnosedan 😊 Thank you. I love the older BMWs. I wish I can turn it into a full time job but for now I can only dream🥺. One question, if you can pick one diagnostic tool as your best "mate" in the garage, would it be the Launch X431 Pad V or something else? Autel may be? Thanks in advance

[@Diagnosedan]

@@TheKeenMechanic the Launch used in this video can do programming on BMW. So when working on BMW i would prefer Launch but in general Autel and Launch are very closely matched

[@TheKeenMechanic]

@@Diagnosedan Thank you. I mostly work on BMWs so your advice is very much appreciated🤝

[@Diagnosedan]

@@TheKeenMechanic you are welcome buddy. Also consider Subscribing to DDTSB we have got many repair solutions for BMW in the program, i'm 100% sure you'll love it. We also have qualified BMW techs on our helpdesk.

[@zonder7284]

man really helping me out right now. my 320i goes into limp mode and now it wont turn iff. ill have to see if this works and if it does your a legend.

[@PineHollowAutoDiagnostics]

Great video and description of operation, Dan! How does this system make the engine more efficient? There is still pumping losses during the intake stroke because the intake valve is only slightly open 🤔 that was a lot of plastic too 😅

[@ferrumignis]

Pumping losses are reduced because the inlet manifold no longer has vacuum. In a normal engine the piston has to do work against the vacuum in the inlet manifold during the induction stroke, and because the inlet valve closes before the compression stroke this work is lost. With the valvetronic engine the piston has to do work creating a vacuum when there is a small valve opening, but this vacuum is contained only within the cylinder so the work is mostly recovered on the compression stroke.

[@Diagnosedan]

Hi Ivan thanks for taking the time to leave a comment. Because the valves open only a fraction of those of a conventional engine in some situations the air has to flow alot faster past the valves to fill the cylinders. The higher airspeed and the vortex that's created results in a better filling (volumetric efficiency) of the engine.

[@PineHollowAutoDiagnostics]

@@Diagnosedan Aaah that makes sense! The airspeed is key :)

[@PineHollowAutoDiagnostics]

@@ferrumignis Interesting theory! To me it seems like the amount of work done by the piston on the intake stroke is the same for either system, just that the restriction is in a different place (throttle body vs. intake valve). Once the intake valve is closed, the cylinder contains the same air mass in either case, so the same amount of work would be recovered on the compression stroke...right?

[@eric49a]

Also throttle response should be better as well since atmospheric pressure is right on the valve at all times instead of having to travel through the intake manifold

[@MrFirdel]

Dan, im addicted to your videos. Your sense for detail is fantastic! Please dont stop!! :)

[@michaelbuela8403]

Always excited for Dan’s new video.

[@Diagnosedan]

Thanks Micheal

[@rayh1965]

Dan, if the test is on a 2 wire motor it is a brushed motor and the high resistance reading to ground could be carbon deposits either on the brush gear or field windings insulation breaking down. It can be a very good test of an aged motor and yes, a faulty one. I'm a former Auto Electrician and now Electronics Engineer so I love your videos, brilliant information, well explained and fun. Keep them coming. Ray

[@Diagnosedan]

You are right! Thanks for watching!

[@andrewvanderwolff1226]

This could also be moisture inside the motor body causing ground leakage, either way the part is not serviceable. Well done Diagnose Dan!

[@Mark-jd1jx]

Great video, I love how great you are at explaining how everything works. Makes it easier to understand.

[@Diagnosedan]

That's great to hear

[@davidhall3747]

Dan teaches that complex things arise from simple rules. Great methodology when explaining how cars work. I just replaced DME 1 & DME 2 on my 2006 BMW 760 I) The Oxygen Sensor Controller chip(s) had failed. No problems with the Valvetronic system yet. The V 12 Engines seem to be very reliable other than the Electronic issues that can occur.

[@Diagnosedan]

The V12 is an amazing engine, i used to own a BMW 850 a loonnnnnggg time ago.

[@davidhall3747]

@@Diagnosedan The V 12 Engine is a smooth running Engine. The Rolls Royce Phantom and the BMW 760i have the exact same 6 Liter V 12 Engine. BMW owns Rolls Royce.

[@Diagnosedan]

@@davidhall3747 i know i've been to the factory and have seen Rolls Royces being Build. The body is build in England and the rest is assambled in Germany

[@davidhall3747]

@@Diagnosedan How long does it take from start to finish to build a Rolls Royce?

[@leonngobeni6735]

Great video Danny, as usual your videos are very informative, I’m a Beemer tech, situated in sa I always have spare valvetronic motors mixed up, now after watching this I realized that there’s actually a way of testing wether if the motor is functional or not. Gonna sort and label them as soon as I get to the shop. Thanks a lot buddy.

[@Diagnosedan]

Let me know how many failed the test😁

[@leonngobeni6735]

@@Diagnosedan definitely

[@st165saj]

@@leonngobeni6735 how many?

[@steveo4048]

Excellent video. My only critique might be the wiggle test. It was very aggressive. Other than that, spot on diagnosis work. 30+ years of fixing cars and my mentor explained to me long ago the benefits and short comings to wiggle testing. I used to wiggle test wiring as aggressively as your video showed, and often had little-to-no success. My mentor then would have pinpointed the issue within 20 min. The problem as he explained to me was my method. Aggressively shaking wires can temporarily reconnect questionable connections, making the problem disappear for a while. He went on to explained wires don't move that much in the vehicle, even going down rough roads at 130 kph. He suggested a far more gentler approach, focusing on areas that round sharp bends near metal engine parts. Areas that could provide an unwanted ground. While I realize that broken wires were not the issue this time, someone with lesser experience attempting to copy your technique, might find your example less productive. That being said, you definitely know your craft. Keep up the great content.

[@Diagnosedan]

In Holland we have got a saying; Gentle healers make stinking wounds. That said, thanks for watching 😁

[@steveo4048]

@@Diagnosedan ouch. In Canada we say those who don't keep an open mind and are not open to continual learning end up like dinosaurs. Futurist and author Alvin Toffler one said people must be willing to learn, unlearn, then relearn to move forward. While I might not agreeeve with what is being said, I never try to discount the spirit of the advice. At the very least, I take a moment to think about what is being said and if rings true. In my career, I've learned that all feedback is good. While I don't always use it, I show appreciation for the input. Good luck with your channel.

[@Diagnosedan]

@@steveo4048 of course i'm gratefull for the feedback. Please dont be offended cause that's not how it was ment. Maybe it was a little lost in translation. What i was trying to say was that somethimes you must not be to gentle if you want to fix something. No disrespect to you or your teacher and his advise. Sorry if it sounded like that!

[@Diagnosedan]

@@steveo4048 it's an old saying that dates from the middle ages. Doctors or healers in that time didn't have medicine like we have nowadays. Somethimes they had to cut away flesh or amputate to prevent painfull infected stinking wounds that could kill someone.

[@steveo4048]

@@Diagnosedan It's all good. Cheers and good wishes. Again. Keep up the great content.

[@ricky613]

I'd be curious to know what the resistance to the motor housing is when it's warm. Being a pulse width modulation actuator, you wouldn't want any resistance to ground.

[@Diagnosedan]

I have not checked🤭

[@peterfitzpatrick7032]

Ricky, I assume you meant to say you WOULD want very a high resistance to ground (in the Mega ohms range)... basically insulated from the body... 🤔

[@johnmehaffey9953]

Dan you’re a genius, like most people I can’t work on or understand modern cars but not only do you describe it so well you go through all the problems that can cause the fault, you help me so much that whenever I do have a car problem I can explain it to the mechanic properly, ps he’s a bmw fanatic

[@Diagnosedan]

Thanks for the great comment John

[@Diagnosedan]

Actronics; www.actronics.co.uk/ Scantool used in the video; Launch X431 PAD V ECU online programming scanner Global link bit.ly/3v0VP9L Ask a question about scantool bit.ly/3gbJtaR DE www.amazon.de/dp/B092LYKYF5 ES www.amazon.es/dp/B092LYKYF5

[@xboxplasma145]

Is this the n46 engine and what year Dan I changed my vvt motor long ago still don't run

[@jotrastad9076]

You never use Texa tester ? Work with Elektropartner

[@Diagnosedan]

@@jotrastad9076 i've never worked with a Texa. Maybe in a future video

[@b577960]

Nice fault analysis but I need to correct you on something. You are partly correct about the purpose of the valvetronic. It’s not there as a secondary throttle control. Throttle control is solely done via the throttle body. The purpose of the valvetronic unit (as you sort of indicated) is to open the valve further to let more air in as the revs rise. Its purpose is to increase power it’s not a fuel efficiency device. As you push the throttle down the throttle body opens, the ECU controls the valvetronic device to give the inlet valves more throw so as to let more air in, the fuel injectors adjust to let more fuel in. The Vanos unit is seperate, it advances the camshaft to open the inlet valve earlier when revs rise. The engine with the faulty valvetronic unit would not reach full power because the valves would not have been permitted full throw. For normal driving this would not have been noticed, but the engine would not have reached its full output potential. Hope this makes sense to you

[@qhew]

Dan, great learning experience as usual. now i understand the valvetronic technology & reason for its use. you are a real master at finding intermittent faults so quickly. the intermittent (temperature-related) failure of a dc (brush motor…my guess) showing as a finite resistance to gnd is interesting & something i would never have guessed as symptom (aren’t such components super reliable? seems not). love the way you whisk off all those plastic engine covers with the cordless & use those fast ratchet ring spinners. why not leave the plastic covers off permanently & save all that work! sure, engine wouldn’t look so good & more exposure to dust & grease. (but that’s a discussion for another day). regarding “valvetronic” technology & using inlet valve opening control instead of a butterfly to control an engine o/p, sounds like a great engineering project! but i worry about the extra mechanical/electrical complexity (& probable less reliability for a (small?) increase in efficiency). i’m curious if other manufacturers too use it. is the increased efficiency mainly at low airflow/output? guess that’s a different discussion for another day.

[@WayToManyAssassins]

The motors are reliable, but can get burnt out from too much heat or eccentric shaft sticking. The motor is made by siemens vdo pretty good manufacturer.

[@bridges5659]

It's no doubt that BMW messed up with the valtronic system especially on the 4 cylinder cars. Most common was the 320i, E90. But you're good at your job, Dan. 👍👍👍👍

[@WayToManyAssassins]

Everything was messed up on the 4 cylinder cars 😂😂

[@davekwiatkowski4531]

Hey Danno, Great to see you again,,, I am chopping on the bit in anticipation!!

[@Diagnosedan]

😁😁Great to have you here Dave

[@henrychitambo171]

Dan I think you're making me a big mechanic, I hope after this video I will be able to fix myN46

[@justatech1990]

Awsome video as always being a young tech everything you did helps me in learning how to diagnose and become a better tech thank you!!

[@ashercohen4739]

Thanks again for the obvious study, you are never in a hurry to replace the part and that is what is special about you

[@Diagnosedan]

Thanks for watching

[@josearmas6938]

As always another master class!!!! Thank You!!!!

[@Diagnosedan]

Thanks Jose

[@tonygovender3805]

Thank you Dan, you are a great technician. Your explanations are very well illustrated and systematic. Blessing to you

[@oldschool1993]

Dan, you been knocking down a lot of bratwurst lately.

[@Diagnosedan]

You sound like my doctor 🤣🤣

[@moestrei]

Winter is approaching in Europe, gotta build up reserves.

[@Diagnosedan]

@@moestrei 🤣🤣👍

[@Nypartcannon]

I’d like to see that resistance reading when the motor was warm and also a insulation tester would show the potential short to chassis in the motor winding. Love this video

[@Diagnosedan]

Thanks for watching

[@sdgelectronics]

I would guess more that impedance is to do with the EMI filter in the motor than a short to chassis. The body is normally tied to chassis ground with a lumped impedance between each terminal and the chassis.

[@Nypartcannon]

@@sdgelectronics Thankyou for educating me

[@JimmyMakingitwork]

They should have BMW valvetronic motors in vending machines. Right next to the oil filter housing gaskets and cooling system parts. ;) Thanks for the video!

[@Diagnosedan]

🤣🤣👍 thanks for watching Jimmy

[@KJ-hp3ut]

That's funny shit right there, yet so very true.

[@svenramsey-hl3mp]

Again good diagnosis but you should wind back the servomotor with scan tool before removing or if function not available wind back manually. There is a 4 or 5mm hex bolt on the back of the motor. Also you should always grease the new motor worm gear and again manually wind into the eccentric shaft to prevent damage to the shaft. Also you really need to replace the VVT relay every time you replace the motor as per BMW repair instructions and as advised through BMW parts catalogue ETK and I also recommend programming the DME too. Just my 2 cents but again great video!

[@petar443]

Man . I Didn't know that your shop do tire services too. Salute mechanic ! 🫡

[@Diagnosedan]

We do everything 😁

[@donaldduck9424]

Briliant video.Valvetronic brillantly explained. Even i understood it.I think your dignose is excellent. The valvetronic motor was the problem in the case. But maybe you have an idea how to fix my problem. My 125i (with 3 Liter N52 engine) runs perfect as long as it's cold. Maybe as long as valvetronic is not active (it works only in case of warm engine does it?) . Valevetronic motor and sensor are new. When the engine is warm , it looks like the car rises the rev's while it's in idle. When it's pretty hot, there are gas shocks (up to 1700 1800 rpm) every 10 or 15 seconds, standig in front of traffic lights. Occasionally the engine stops runnig and throws a air mass meter faultcode.I wish i had someone like you next to my location.

[@matusekpetr7806]

That low resistance between body and terminals is most likely caused by conducting dust from motor brushes. Its definetelly not OK. If there will be short circuit, then it blowns fuse, what i expect to be the root cause are already worn out brushes, causing open circuit on terminals after some circumstances. BTW, thanks again for the nice explanation of valvetronic system Dan !

[@Diagnosedan]

Thanks for sharing sounds plausible!

[@soundseeker63]

Now thats how to diagnose faults properly! The heat test and the pin-case resistance test was very interesting, clealy it located the fault, though I'm curious as to why heat would have made the motor inoperable...? A post-mortem examination on the old motor would have been cool as it might have revealed the cause of its erratic behaviour.

[@kameranlhoni410]

Hi Dan. I have a similar BMW E90 2009 LCI N46N 4 CYLINDER engine. I am suffering from high oil consumption (One Litre per 1000 km) and also the engine oil is getting contaminated and very dirty within 200 km ( I am using Liqui Moly 5 W 30). I have changed the PCV valve diaphragm with the spring. The PCV is located on the valve cover & the engine has 182,000 km. I have replaced the valve stem seals before 5,000 km with new head gasket, But i am still having oil consumption & both suction on the oil cup when opening and high pressure when the oil cup is open. Beginning of this summer I removed the Thermostat as I am living in (Kurdistan-Iraq) where ambient Temperature reaches 47 °C. Now engine coolant Temperature is around 78 °C where the Thermostat is opening on 105 °C ( I will put back the thermostat tomorrow and update you). I will appreciate any suggestions and diagnostics procedures.

[@mr_nice.]

Looks like piston rings, but I'm just speculating.

[@Diagnosedan]

You proberbly have leaking valve seals

[@kameranlhoni410]

@@mr_nice. I will do both dry & wet compression test to verify the condition of the rings.

[@kameranlhoni410]

@@Diagnosedan I changed the valve stem seals with new head gasket before 5,000 km .

[@D989501L]

Hi Dan, nice to seeyou back, don't leave it soo long next time 😁, you must have nerves of steel undoing two 10mm nuts without anything underneath to stop them falling down the cylinder head I know they would end up their if I did it. Regards Richard 🇬🇧

[@Diagnosedan]

Hi Richard, the nuts wouldn't have fall very far😁 thanks for taking the time to leave a comment it's really appriciated

[@D989501L]

Always informative and I learn something every time. Hope you are all well. Regards Richard

[@Ivo--]

Best explanation on the internet!

[@diyknutti8220]

Glad to see that this car owner picked the best mechanic in firstplace, so they dident loose Money in a bad shop. :)

[@Diagnosedan]

Thanks!😁👍

[@soranghafour]

Every time DD upload a video it’s a informative and educational from master Dan , great explanation

[@Diagnosedan]

Thanks Soran

[@stevekelly5166]

Nice to see you back - seems some time since a new video appeared. (Subscriber). I like how you talk through the problem and spend less time of every individual nut and bolt. Or I've got a scan tool. You explain things logically. And DID IT AGAIN.

[@lul27]

I am always learning from Dan, I'm not a mech but I'm going to school for it now. Hope I can catch up

[@Diagnosedan]

Good luck in school! Study hard💪

[@tomek860]

Another great video 👌 But one thing that surprises me is that the procedure that you have followed to find the issue is not really complicated, you read the codes, checked what they have indicated and boom - car fixed. There was not need to use some secret methods know only to shops dealing only with bimmers. How come other shops failed to fix it? I would think that a shop knows how do read codes and check the issues that are indicated. It was basically checking what your scanner said - the valve.

[@Diagnosedan]

No you are right this fault was not really complicated, but because it was intermittent it was a little bit more challenging.

[@arthurmajor952]

Hey Dan Great video for us bmw owners, i brought this scanner autophix 7910 it's a pretty inexpense scanner i would sure like your to do a review on this scanner, it has special function and valvetronic reset plus many other special function, thanks for the understanding of how to diagnose valvetronic motors again.

[@elliottness6810]

Good day. I was following your videos and I attempted to remove and replace a n42 engine from 2002 BMW coupe. I removed the cylinder head, replaced the head gasket, bought the timing tool and followed the instructions. I attempted to start the vehicle and it cranked but no start, I then found that the fuel pump was bad so i replaced the fuel pump, fuel pump housing and also clean the gas tank from gunk build up. I also replaced the fuel filter. after al this I attempted to start, it cranked but no start so I removed cylinder 1 coil pack and cranked with a screwdriver inside and it sparked. I have spark at least from one cylinder so I assumed all has spark, I also have gas to the fuel rail. I think I need to test the other 3 coils, and also if each injector is spraying. I attempted to prime the system with a little gas at the intake while cranking and found that it was pushing air out the hose on the intake, these hoses normally suck air so am assuming that my timing is off. but how come, I used the timing tool properly I am assuming. what's you input.

[@CumminsDriver100]

Excellent explanation sir! As I watched this video questions would come up in my mind, and then you'd answer them right after! It was as though your scan tool was connected to my brain, showing you the data inside. Lol. Miss your videos when you don't upload for long periods of time!

[@Diagnosedan]

Yes it's been to long ago.

[@Pete-in-Essex]

Good stuff Dan. I reckon the motor showing a high resistance breakdown to earth / ground is not conclusive proof of the intermittent go / no go fault, but it needs replacing anyway. Looks like a nice clean and well maintained engine.

[@rkan2]

We need a teardown of the motor to find where the conducting happens!

[@karelrysavy334]

great videos! :-) You represent the best of the States or America (as we like to call it in CZ, Europe) has to offer, friendly, open and honest, informative, helpful.. If I were in the States (again) I'd come buy You a beer and possible buy a used bmw from You ;-). K.

[@battlehrfred]

Hi Dan! great thorough explanation and excellent detail! i have a QUESTION ? for example you change out a leaky top oil valve cover pan and gasket on a 2012 x5 n55 E70 SUV and you have removed the valvetronic motor, should you do the "relearn procedure" BEFORE you try to restart the engine, or does it make a difference or would it still just start up fine without any isssues?? ty please continue with great diagnosis videos!! ty

[@claudioagmfilho]

🇧🇷🇧🇷🇧🇷🇧🇷👏🏻, Dan you’re the best wow! I wish we had guys like you down here in Brazil…

[@kevace1985]

Yes as a Multi craft tech for a production plant here in USA any resistance from a motor lead to ground is a sign that the motor is about to go. Although I mostly deal with 3 phase AC motors, DC motors are much more prone to intermittent issues as it's only 2 poles, and stepper motors, such as that for Valvetronic, need a clean current path to work properly. We use a "Megaohm" to check motors for this on the industrial side of the industry

[@Diagnosedan]

Thanks for the feedback Kevin!

[@abhijeetrode]

Super!! Every time I watch your video, I learn something new. Keep it up 👍

[@rwd323]

Great video, it does amaze me how many mechanics are unwilling (or unable?) to diagnose faults, we see cars almost daily from other workshops and many of them are not difficult to diagnose

[@Diagnosedan]

We can always diagnose and fix any Car but some just take a little longer 🤣🤣

[@samathman3937]

As an Electrical Engineer (though motors are not my specialty) I would say that you are correct in that your test indicates a failed motor. Probably a heat related insulation failure.

[@darylwalford8697]

Another very interesting video, I've just been working on a 2008 M3 S65 V8 with a Vanos problem on the inlet cam of bank 1, turns out the Vanos unit had totally failed. Thanks Dan, your videos help us diagnose tricky problems.

[@Diagnosedan]

Thanks Daryl, i love making video's just for getting feedback like this. I love when my video's help others

[@jeremyjames3916]

Just changed one on freinds 2006 Rag Top on Tuesday for S/H one. Going to do Ohm's test on old one Tomorrow. I would have liked to test S/H one before fitting had I known. Great Tip.Thankyou Kindly.

[@Diagnosedan]

Let me know what you found!

[@TheYO7A]

Welcome back.. Don't stop the good content coming. Thanks

[@Diagnosedan]

Thanks!

[@diamondjaguar]

Excellent explanation. What scan tool are you using?

[@PhongTran-jc7hw]

Thank you very helpful video. I like it. I am a bit confused is the control signal of Valvetronic servo motor is PWM pulse waveform? Hope you have 1 actual test video.

[@mikechiodetti4482]

I've never worked on one of these. I like the theory of operation. When you said the throttle is usually open, that reminds me of the old non computerized diesel engines. The injector pump controlled the idle.

[@Diagnosedan]

Thanks for the comment Mike it's appriciated

[@dilink23]

My first time watching and this man I a great Teacher

[@smc9764]

I really liked this video and thanks for your time. Do you have any tips or suggestions on the third generation valvetronic motor that is buried in the cylinder head? I have 328i with n26 motor that is giving me intermittent errors. I was thinking of using a scope for the very first time to check the signal wires, but wondering if you have any pointers or tips?

[@andybonneau9209]

Bleeding power to ground through the motor housing is never good. About 5 mA at charging voltage, but probably much higher during fault. Heat the motor up and the measure the resistance. I bet it will go down. Great video. Thanks.

[@2secondslater]

I have been getting into the valvetronic system on an S63TU from an M Sport X5 50i whilst replacing the valve stem seals because of a smoky engine, it is not a very complicated system as most people think it is.

[@LuisVasquez-w6c]

Great video Dan! Im looking forward on replacing the valvetronic motor on my n52 engine myself. However, how exactly do you relearn the motor so it knows whats fully open/closed??

[@go5582]

diagnoseDan is the Man. great job Dan. Im from California USA, and Im considering getting a BMW 2022-hybrid. which hybrid brand would you recommend?

[@orlanmedina3693]

Always the best! And agreed makes sense that the copper wires insolation starts pealing off and therefore failing so the ohm test it's a good test

[@Diagnosedan]

Thanks for the comment!

[@mkaestn]

I got this system in the N52. Lots of low RPM torque compared to the M52 six. No problems after ten years and looks easy to repair.

[@Diagnosedan]

That's great to hear Mark

[@paulmunteanu3186]

Very professionally done this video. Congrats!

[@GBR4ME]

You were missed, welcome back.

[@Diagnosedan]

Thanks Steve also great to have you here again

[@darrenmurphy6251]

the resistance to the casing could be one of 2 things ,there should be noise suppressor capacitors built into the brush assembly and they send the noise to earth = the motor casing , so if one of those capacitors goes leaky or short your readings will show that or an overheated rotor winding with now compromised insulaton, the rotor core would get earthed via the bearings but in both cases i would expect the diagnostics to say "motor short to ground , intermittent " or "motor over current" so im not sure but then that resistance needs to go lower to be an issue, maybe it does when the motor is hot?

[@andrewevans2453]

Hey Dan your knowledge and logical thinking always amazes me. I’m a tech i Ian and have been looking at buying my own scan tool. What’s your opinion of the bi directional controlling autel models? Or would you recommend another scan tool.

[@Diagnosedan]

Autel or the Launch used in this video are great scantools

[@khefer1980]

Very good tutaorial sir. But I have a question: when motor was failing you see errors in computer - were these errors visible before you started your activities?

[@SerbanCMusca-ut8ny]

Each and every of your videos forces the respect. Thank you for the clear explanations and the interesting content!

[@Diagnosedan]

And thank you for watching and leaving a comment!

[@davidellenbaum1229]

yes good test . failed motor . you as usual went the extra mile . thanks for sharing. learned something new. again thanks dan

[@Diagnosedan]

Thanks David!

[@arthurfricchione8119]

Dan your videos are so well explained. Like I’ve said many times I’m just a retired. Diyer ( retired aircraft ) but enjoy all of your videos. I’ve also just signed up for classes. With one of your country men friends D. Quinn. Just like learning all I can. Thank you for sharing. Would join your tech support group but seems to be more oriented to shop owners. Anyway thank you for sharing and stay safe and well Artie 👍👍👍

[@Diagnosedan]

Hi Artie, great to hear from you in the comment section again. It's great to hear you still engaged in learning! Best regards Danny

[@hommadi2001]

Great video as usual :) Absolutely yes, if the insulation failed the motor is gone. Just the other day I had a similar issue on a coolant temp sensor on my car. While it was out of the car, worked fine. When screwed in it did not! Turned out it had lost the isolation between its two terminals and chassis.

[@Diagnosedan]

Thanks for the feedback!

[@engeneer_ru5827]

Thanks for the fan failure analysis. A typical problem in modern pulse electronics. The appearance of the resistance of the terminals to ground is the graphite dust from the brushes. Perhaps this motor is PWM controlled with leakage control to ground?

[@Diagnosedan]

Thanks for sharing!

[@KJ-hp3ut]

Very well explained and the details in fixing the issue is top notch. I would like to know though the Total man hours @ what rate and the total bill if possible. Also if that rate is dealer or private. Awesome video though

[@dapeco59]

Excelente. Y que medidas debe tener el eje excéntrico en RALENTÍ y acelerado? Mirando en el escáner

[@johnclarke6542]

Great video Dan I believe random engine check light on BMW's is standard equipment

[@Diagnosedan]

🤣🤣👍