[Alexxxxxxc]

Hi,
First post here so please excuse any formatting mistakes etc.

BACKSTORY
Purchased a 15 plate 318D Auto back in November 2019 when the weather was cold and everything was sound with the car, fast forward to summer 2020 when lockdown began and the massive 2 month heatwave followed. Due to us not going out at all really it wasn’t until I started going for longer journeys (1hr+) that i noticed some slight knocking coming from under the front of the car that could be felt through the pedals and steering wheel (slightly), weird, so i did a lot of google/forum diving and the common thing that came back was control arm/cv joints.. however, what I noticed was that a lot of the common diagnoses for control arm issues etc meant that the knocking sound had to be constant, which it wasn’t.

I noticed that on hot days (15c+) the knocking would start, driving in ambient temps of 15-20c would take up to an hour for the problem to start occurring whereas temps of 20c+ the knocking would happen within 15-30mins.

Took it to my local garage who have always been great with my previous cars struggled to diagnose the issue, they drove the car whilst it was knocking because they had never heard of an issue similar (related to weather). They were adamant it was roll bar bushings and replaced the roll bar with oem one (under my permission).. this did not fix the issue and they were left slightly stumped. They did not charge me for the part or labour so thumbs up.

My dad who is handy with cars had a look at it and suggested it would be the control arms. He got me to sit in the car after the knocking started whilst he pushed the front end up and down (this did not recreate the knocking effect) and then rocked the car forward and backwards which did recreate the knocking effect. He said if it were the suspension or top mounts then bouncing the front end up and down should have recreated the knock.

By the time i had a bit of savings behind me to pay for another garage visit the weather was cold again and the problem went away.

Now the weather is back to 20c+ it has definitely gotten worse, the knocking sounds really bad and starts after a few minutes in hot weather. I want to try and sort it this summer because by the sound it made the other day it felt like something was about the break or fall off.

Is there anyone that could offer me with advice on how to approach this or what the problem may be? I don’t really want to go back to the local garage even though they have been previously good because they were honestly stumped, they said the next thing would be to just change loads of parts in the hope it would fix it (top mount,arms,cv joint).

SYMPTOMS
1. Knocking sound/feeling in hot weather, gets worse as temp gets hotter (15-20c+)
2. The sensation of knocking/clunking can be felt through the pedals and steering wheel.
3. Cannot be heard outside of the car.
4. Bumps/Turning doesn’t seem to have an effect on the issue, i.e it doesnt sound/feel different to just driving in a straight line over smooth roads.
5. Knocking can be felt massively at speeds below 30mph, the faster i go the less noticeable it is, especially on motorway i can’t feel it at all.
6. When I apply the brake steadily the noise/clunking feeling sometimes feels softer.
7. When reversing the knocking sound/feeling is almost non existent. I’ve only noticed it a few times when reversing and even then it was very muted compared to when in drive mode.

The reason I highlighted the last point was because this is something I don’t quite understand and maybe leads me to believe it might be a gearbox/transmission issue?

Any help would be greatly appreciated.
Thanks,
Alex

[Andy350]

I have the same problem, unfortunately not a solution

[transcendid]

2020 m340i RWD, adaptive suspension. Same issue here started under 10k miles. Quiet all winter. Back with warm weather in Northeast. Dealer never able to replicate it, but did replace left control arm per TSB, no effect. Still searching for solutions…

[Rickf31]

Hi - Ive had the same problem for 4 months, garage couldnt find anything after 2 visits and a test drive. I found a BMW SIB, known fault with an original manufacturers part. Affects F22, F23, F30, F31, F32, F34, F36. If you are within warranty the fix for free, mine was a year out of warranty, £250 bill from independent garage but fixed.

SIB 320819

Get you tie rods replaced and you're good.

Worse thing is its a BMW SIB and they never hold their hands up, and wont fix when your out of warranty even though they know the part needs replacing

[Andy350]

Thank you man. It is so nice that there is commimuty and we can help each other not to spend crazy money on solving by changing many parts.
I have called to bmw service. They suggested it could be brakes etc etc.. so I told them to take my VIN and put it in to system firsto check for such SIB. Of course then they called me and told me there is such known issue. So to be honest as my girlfriends father owns an indipendent service I will get it done there and update it here.. if it helped. Keep my finger crossed also for others to solve it. In my opinion the car is perfect and I love it.. (F30 2017 B47)

[Mahmoudb]

Hello everyone,

I have the same issue on my car, no sound when cold weather and when the temperature is up to 25 degree C I have a knocking noise from the front

Any help please

[Rickf31]

Andy350 this is the SIB / TSB for info

https://static.nhtsa.gov/odi/tsbs/20...66230-9999.pdf

Mahmoud B get your tie rods replaced. Garage may look at them and say they are good, thats what the garage told me, but if they are manufactured by CTR and you have ZF steering and the fault is when the engine is warm / hot weather - SIB / TSB says it all

[Mahmoudb]

Originally Posted by Rickf31

Andy350 this is the SIB / TSB for info

https://static.nhtsa.gov/odi/tsbs/20...66230-9999.pdf

Mahmoud B get your tie rods replaced. Garage may look at them and say they are good, thats what the garage told me, but if they are manufactured by CTR and you have ZF steering and the fault is when the engine is warm / hot weather - SIB / TSB says it all

Thanks you very much Rickf31 for this document
My bmw dealer says my tie rods are good...
But I totally agree with you the TSB SAY that !

[Andy350]

Local garage told me as well that tie rods are good... However it is owned by gf father..so I showed him this.. we ordered lemforder tie rods.. changed it.. yesterday i got the car and it was 38 degrees Celcius here in Slovakia. I drove for a hour..then left it on sun and continued. the car is and remains perfectly quiet. Thank you guys.

[Rickf31]

Originally Posted by Andy350

Local garage told me as well that tie rods are good... However it is owned by gf father..so I showed him this.. we ordered lemforder tie rods.. changed it.. yesterday i got the car and it was 38 degrees Celcius here in Slovakia. I drove for a hour..then left it on sun and continued. the car is and remains perfectly quiet. Thank you guys.

Glad it worked. Shame BMW don't actively share the fix / problem so people can get their cars fixed without wasting money trying to find out what is wrong

[Mahmoudb]

Hello,

I’m coming back to you
Finally my bmw dealer hear the noise from the steering rack (EPS) so I advise is from tie rod. Actually my car is under warranty so Bmw dealer proceed to change the complet steering rack system EPS And finally I’m good without any noise when is hot
Thanks you evry body for your help !

[transcendid]

Does anyone know if this could be affecting g20 as well?

[transcendid]

https://www.bimmerpost.com/forums/sh...php?p=29919119

Tsb finally available!

[1seriesApr2016]

Originally Posted by Rickf31

Hi - Ive had the same problem for 4 months, garage couldnt find anything after 2 visits and a test drive. I found a BMW SIB, known fault with an original manufacturers part. Affects F22, F23, F30, F31, F32, F34, F36. If you are within warranty the fix for free, mine was a year out of warranty, £250 bill from independent garage but fixed.

SIB 320819

Get you tie rods replaced and you're good.

Worse thing is its a BMW SIB and they never hold their hands up, and wont fix when your out of warranty even though they know the part needs replacing

I have the same issue with my bmw f20, seems to make that knocking clunking sound and it can be felt through the steering wheel as well as the brake paddle where it’s not so obvious on the break paddle . Would the tie rod fix work and make the sound go away , it’s a 2016 model 1 series .

[max7bg]

Hi,

Same symptoms here with my 2015 F20. Mechanic replaced both link stabilizers but the issue remains.

I've asked people that know the matter and they suggest it is either Anti roll bar bush or more likely Control arm bush. Mechanic said rubber inside Control arm bush has cracks and it probably expands in hotter weather as I've only heard the crackling above 30c temperature.

I now have to wait for it to start happening again and then mechanic will try the car himself to find the cause. Will keep you posted.

[sleeprequired]

Originally Posted by Rickf31

Andy350 this is the SIB / TSB for info

https://static.nhtsa.gov/odi/tsbs/20...66230-9999.pdf

Mahmoud B get your tie rods replaced. Garage may look at them and say they are good, thats what the garage told me, but if they are manufactured by CTR and you have ZF steering and the fault is when the engine is warm / hot weather - SIB / TSB says it all

The pdf mentions a video under the procedure heading. I can’t find a link on the document am I missing something?

[Jimmert]

Originally Posted by max7bg

Hi,

Same symptoms here with my 2015 F20. Mechanic replaced both link stabilizers but the issue remains.

I've asked people that know the matter and they suggest it is either Anti roll bar bush or more likely Control arm bush. Mechanic said rubber inside Control arm bush has cracks and it probably expands in hotter weather as I've only heard the crackling above 30c temperature.

I now have to wait for it to start happening again and then mechanic will try the car himself to find the cause. Will keep you posted.

Problem sits in the inner tie rods, so not the link stabilizers. They are hard to diagnose, you don’t feel any play. But in my case replacing them also fixed the knocking problem.

[AARON1569]

Anyone get a definitive answer on there issue, OP never update?