Valvetronic isn't gearbox, it's the variable intake valve lift, from 0.3 to 9.9mm. They use valvetronic instead of a throttle butterfly to control air intake.

Poorly valvetronic system usually results in low power, and/or reduced economy. Sounds like it's warranty time?

 

Warranty? It's a private sale, used car, 2012. Loads of people mentioning the valvetronic and adaptations link that's all. Isn't it to do with driving behaviour and throttle response so linked that way?

 

You can reset adaptations with no equipment I thought

https://www.1addicts.com/forums/showthread.php?t=501246

 

I don't know how relevant they are for a DCT transmission and also a "push key" rather than a turn key. The instructions seem a bit naff and I imagine doing it with software is the better option.

I tried ignition on, gas - foot to floor for 30 secs - off gas, ignition off, restart. Etc. Not sure it's made a difference to anything, not sure.

 

Time to invest in a decent code reader or take it to have it reset properly by a garage as I think normal garage grade scanners should be able to do it either that or see if someone local to you has ista that will help

Without trying to sound negative I'd start saving for the valvetronic parts as odds are the previous owner has had it reset and that's why the car was for sale

 

I'll get it checked.

I know why the car was for sale, wasn't due to this though.

He assures me he's not done anything and it has had a fair amount of work done this year so I'm giving him benefit of the doubt here. The problem hasn't returned yet, but there are codes present. I'll get it on a friends ISTA tomorrow and see if anything else pops up.

 

I've just found history of valvetronic actuator and eccentric shaft, DME recode, set the stops and adaptations, timing chain kit - January 2019. £3k inc vat.

Sound like it would need doing again this soon?

 

Yeah, you've got to ask yourself why the car was already warm

Can he take it back though ? It was a private sale, you may get a decent seller but technically they can refuse to refund can't they citing sold as seen

 

the fault wasn't there when i test drove it and used it numerous times prior to the error showing the first time

the car warm because he drove to work in it and i viewed it at his work not long after. i would like to think not everything is smoke and mirrors. the guy who bought my m140i recently inspected it when it was red hot, as i'd gone to meet him at a train station.

i have read something about a battery change in conjunction with this error, and sure enough the guy had a new battery not long ago. i've recoded it, done over 120 miles now, started/stopped/from hot/from cold. absolutely no errors now showing.

asked a specialist too for their advice, they said it isn't common and wouldn't expect it to be that after the previous invoice for £3k 28 months ago. they also mentioned battery voltage which i thought was a load of rubbish but it seems to have sorted it.

will report back, but so far, seems fine!

 

Hope it's gone for good. Post up some pics of the car, let's see it

Maybe slap a BMW warranty on it for peace of mind ?

And don't start torturing yourself by looking for BMWP parts for it as they are hens teeth these days 😄

 

the fault wasn't there when i test drove it and used it numerous times prior to the error showing the first time

A quick reflash of the ECU will make pretty much any fault go away for a while, they will come back though

Ive heard of it before, a mate bought ........... yours is a white N55 DCT, right?
How long had the guy owned it before you had it, it cant be the same car surely .......

https://www.babybmw.net/forum/viewtopic.php?t=116862

- FWIW I know Rubix (utterly sound guy) and the place it went afterwards (pretty sound too TBH), PM if you want

Anyway, its not entirely unheard of, it seems its either a look or an eccentric shaft issue when it happens but Id doubt yours would fail that quickly, some links:

https://www.1addicts.com/forums/showthread.php?t=1648511

https://www.e90post.com/forums/showthread.php?t=1333614

https://f30.bimmerpost.com/forums/showthread.php?t=1507594

Good luck, hope you get it sorted

 

I've just found history of valvetronic actuator and eccentric shaft, DME recode, set the stops and adaptations, timing chain kit - January 2019. £3k inc vat.

Sound like it would need doing again this soon?

Yeah that was a sore bill after owning the car for 3months

I hope you get to the bottom of this, my advice if it keeps showing up get it checked by BMW or a specialist. I had a shadow error about the valvetronic until one day it fully shut the car down in the middle of my town, at christmas and the DCT wouldn't get out of park. It was pain! I sold the car last year but I can say from Jan 2019 to Jun 2020 it drove with no codes and drove well

 

Apart from it not showing any error codes on the dash or an OBD, it also needs to be sold while "unroadworthy" which a dash light probably doesnt constitute.

You need to be able to prove the seller knew there was a fault, I think youre going to struggle here if you go down that road.

 

I got the car for a decent price, so even if I had to shell out for the valvetronic again, it isn't the end of the world.

However I'm using the car as normal daily and done lots of different trips and the codes have not reappeared as of yet.

Spoke to a few people too including previous owner(s) and garage who did the previous valvetronic work a few years ago so I know where I'm up to.

 

I've actually found a huge thread on E90post about the N55 x35i engine, and MHD maps, and links between the Valvetronic errors. Mine is MHD Stage1.

I'm going to revert it back to Stage0 OEM map if the problem reappears. Few people look to have the same problem regardless of replacing the Valvetronic bits:

https://www.e90post.com/forums/showthread.php?t=1101331

, post 33 onwards starts linking between MHD and the codes

 

Update, October (3 months later):

Car is still behaving completely normal, being used every day, and as a precaution I had it at 2 different specialists since buying it who have both said nothing is wrong with it and the valvetronic system is fine (and no woodpecker noises from it either on unlock).

One indy said they have seen codes stored in memory when modules have been messed with or recoded without the errors being initially cleared first. With my valvetronic £3500 bill in the service history from past owner, it looks like they reflashed a module at the same time, so might be related to this. Also some codes apparently need BMW software (would that be ISTA?) to clear them properly (forever) rather than "cheap" code readers.

I'd previously used Carly to clear the codes when I picked the car up.

Basically, whatever error codes are on the car now, I can clear them with ignition on (but car not running) and all except the valvetronic ones disappear. Same with it running. It seems like the valvetronic ones are soft permanently stored codes that you can't clear. <shrug>

However, one thing I did notice when I bought the car was a whooshing noise at low speed/low revs, I looked into it and most people said boost pipe would be on it's way out but I checked it and it looked OK and a friend said I'd know immediately if it was a boost pipe leaking as EML would flag. But fast forward about 200 miles and it blew completely at 80mph on the motorway. Luckily the metal retaining clip landed on the undertray and I managed to salvage that, and fitted a new MTC one. Car seems a million miles better since then particularly cold idle and jerkiness from a cold start drive-away.

Still running the MHD Stage1 map without issue. I did a reset of a few bits in MHD actually including the idle and that made it a lot nicer from cold too. Worth doing if you're DCT/mapped.

 

N55 is quite unreliable engine due its updated oil regulation system, if you bought car with N55 you should be ready shell 5000 for used engine and works to replace it
the Valvetronic motor is also well known problem and it is easier to remove it and check how its activating.

 

N55 is quite unreliable engine due its updated oil regulation system, if you bought car with N55 you should be ready shell 5000 for used engine and works to replace it
the Valvetronic motor is also well known problem and it is easier to remove it and check how its activating.

did you read any of the thread or just skim through the first post and reply?

the VT has been done already. there's no symptoms with the car.

i've had N55's before for years without issues.

 

N55 is quite unreliable engine due its updated oil regulation system, if you bought car with N55 you should be ready shell 5000 for used engine and works to replace it
the Valvetronic motor is also well known problem and it is easier to remove it and check how its activating.

did you read any of the thread or just skim through the first post and reply?

the VT has been done already. there's no symptoms with the car.

i've had N55's before for years without issues.

do you believe that bmw parts are eternal ?
if you have this code you have to check wiring or motor, anyway
i understand the every used bmw owner hope that someone already did maintenance and he will not have problem with that part anymore
but in reality (owning e46 from 2010, e91 from 2012 and e81 from 2020) this is not true
i lived in lithuania many years, and have contacts with junkyards, and N55 is most popular and very pricey (around 5k euro) engine due multiple engine failure. in comparsion the N52B30 engine cost 800-1000 eur on junkyard because it is quite reliable
one member of belarussian bmwclub owning e82 n55 dct already did n55 rebuild 3 times

 

here is special thread for you

https://www.e90post.com/forums/showthread.php?t=1513898

i'm longtime e90post.com forum member, but since i own e81 european i found that babybmw is particular useful for european 130i and thats why i'm here

 

here is special thread for you

https://www.e90post.com/forums/showthread.php?t=1513898

i'm longtime e90post.com forum member, but since i own e81 european i found that babybmw is particular useful for european 130i and thats why i'm here

Thank you for the link.. but on all 19 pages of that thread, there's not a single mention of valvetronic issues.. it's almost entirely unrelated to this thread? I've not got component, oil, pickup, pressure or bearing problems. So to say I should be budgeting £5k for an engine that runs perfectly is not the best advice at this stage

I appreciate you replying but it doesn't really offer anything to this other than "N55's might need replacing", but any engine can need replacing dependant on their circumstance. Nothing here points that way in the slightest.

I know about the N55 and oil starvation / sump, oil pressure, bearings, etc etc, but none of these apply to this vehicle and have no bearing on the error mentioned. I've had these N55's before for a pretty long time in some form or another. I've had sump, pump, pickup, pressure errors on other N55's so know about it.

All I was showing was that despite soft valvetronic errors showing for thousands of miles (in error log, not on control check/display anywhere), it isn't clearable properly without the right software. Like I said, valvetronic motor and eccentric shaft was done 2.5 years ago.

This is more lending to Valvetronic codes being kept in system despite replacement / error-free running.

The indy's I've spoke to said to do the valvetronic twice in such a short period of time is unheard of. I would also have woodpecker noises almost immediately when the problem started to arise, followed by difficulty starting the car, and failure thereafter.

I'll see how it progresses, but as it stands the car is in daily use, done plenty of miles in plenty of circumstances and nothing has given me problems (bar the boost pipe exploding which I knew would happen anyway) <shrug>

 

ok, i'll give more hints that N55 ECU (MEVD1729) can burn it's valvetronic control circuit (or any other control circuit) if someone is doing maintenance on injectors or coils and didn't fixed coils grounds wire back properly, because in that situation ground of other devices connected via ECU will be used.
so you may consider to get new MEVD or tested one, clone it from experienced BMW electric and replace to check if error will go away
there is also case when performed engine washing, this ECU can get water(it is alredy located on engine cover and not in closed box), but i think engine washing is not very popular in UK or west europe.

 

ok, i'll give more hints that N55 ECU (MEVD1729) can burn it's valvetronic control circuit (or any other control circuit) if someone is doing maintenance on injectors or coils and didn't fixed coils grounds wire back properly, because in that situation ground of other devices connected via ECU will be used.
so you may consider to get new MEVD or tested one, clone it from experienced BMW electric and replace to check if error will go away
there is also case when performed engine washing, this ECU can get water(it is alredy located on engine cover and not in closed box), but i think engine washing is not very popular in UK or west europe.

could be related, not sure, but it's not like there is a physical problem so I am leaving it alone for now. I don't know why the ECU was even touched unless it has to have something done to it after a valvetronic motor/shaft change. But it's on the invoice that they had something done to the ECU, like a reflash or reprogram or something. The indy said it'll be more than likely related to the reason the codes are remaining there despite there being no problem.

 

well, i've read other forum and there is relay between ECU and valvetronic motor, you can search and try to replace it
otherwise you have to replace ECU if you are sure that valvetronic motor is working

 

one member of belarussian bmwclub owning e82 n55 dct already did n55 rebuild 3 times

If youre rebuilding the same engine 3 times the problem is almost certainly not the engine

I dont know why things should be different in Lithuania but the N55 is considered a pretty strong engine here, definitely more so than an N54 or an S62.