335d not accelerating smoothly

[elise2000]

Hi

My 2018 335d xdrive (chipped) isn’t accelerating smoothly from around 60ish upwards. Slightly juddery.

Any ideas what the cause may be?

Many thanks

[d_a_n1979]

Don't guess; get it plugged into diagnostics (ideally ISTA, but the likes of the Creator C410 or Bimmerlink will work well also) and see what codes are stored...

It could be all sorts!

[elise2000]

d_a_n1979 said:

Don't guess; get it plugged into diagnostics (ideally ISTA, but the likes of the Creator C410 or Bimmerlink will work well also) and see what codes are stored...

It could be all sorts!

Sorry, should have said in the original post- it’s been to the garage and no fault codes showing

[Crusoe]

Sticky brake probably the most common cause at this time of year, enough torque that you don't notice but cause a wobble at higher speed if it is stuck on a bit. Check wear on your disks, heat coming off them and if any of the wheels are collecting more brake dust. Once you rule that in or out it could be a bent or out of balance wheel (lots of potholes out there just now) or suspension bushes.

[elise2000]

Crusoe said:

Sticky brake probably the most common cause at this time of year, enough torque that you don't notice but cause a wobble at higher speed if it is stuck on a bit. Check wear on your disks, heat coming off them and if any of the wheels are collecting more brake dust. Once you rule that in or out it could be a bent or out of balance wheel (lots of potholes out there just now) or suspension bushes.

Thanks.

Bushes replaced last month so not that

[d_a_n1979]

elise2000 said:

Crusoe said:

Sticky brake probably the most common cause at this time of year, enough torque that you don't notice but cause a wobble at higher speed if it is stuck on a bit. Check wear on your disks, heat coming off them and if any of the wheels are collecting more brake dust. Once you rule that in or out it could be a bent or out of balance wheel (lots of potholes out there just now) or suspension bushes.

Thanks.

Bushes replaced last month so not that

Just because bushes have been replaced doesn't mean they've not failed already. More so if cheap ones were used and/or they weren't torqued down properly, under load!

Don't dismiss anything

[elise2000]

d_a_n1979 said:

elise2000 said:

Crusoe said:

Sticky brake probably the most common cause at this time of year, enough torque that you don't notice but cause a wobble at higher speed if it is stuck on a bit. Check wear on your disks, heat coming off them and if any of the wheels are collecting more brake dust. Once you rule that in or out it could be a bent or out of balance wheel (lots of potholes out there just now) or suspension bushes.

Thanks.

Bushes replaced last month so not that

Just because bushes have been replaced doesn't mean they've not failed already. More so if cheap ones were used and/or they weren't torqued down properly, under load!

Don't dismiss anything

Thanks for reply.

It’s been doing it since before they were replaced though. New tyres at same time as well

[paradigital]

And new (or louder) noises? When you say juddering, does the car still accelerate with a decent turn of speed/force or is it noticeably slower than before?

If it’s slower than before them I’m going with an issue holding boost pressure, with an outside second guess of fueling (be that pressure or a dodgy injector).

[elise2000]

paradigital said:

And new (or louder) noises? When you say juddering, does the car still accelerate with a decent turn of speed/force or is it noticeably slower than before?

If it’s slower than before them I’m going with an issue holding boost pressure, with an outside second guess of fueling (be that pressure or a dodgy injector).

It’s still pretty quick. Wouldn’t say that much slower at all.

But instead of a smooth feeling of constantly pushing forwards, there’s a slight hesitation, almost a tiny break, every half second or so.

[E-bmw]

Are there any associated noises that may indicate a DMF issue?

[FlyingPanda]

Funny enough, I had a conversation with a good Indy specialist that asked me if I’d ever had this (ie: the symptoms you describe) because he’d spotted that I had non-approved tyres on. I said that this all sounded like a bit of tyre marketing snake oil, but he mentioned that the x-drive with a staggered set up (like on a 335d) can get really fussy about even a tiny mismatch and the star-marked tyres are the only way of being sure you’re OK.

I still dismissed it as I have no such issues (Vredenstein Ultrac Vortis) but this just made me think as you mentioned new tyres. Is this when it started?

[Pica-Pica]

Does it seem slow in changing gear? Maybe it’s the auto trans. Does it occur when using manual mode? Does it occur in all auto modes (Eco/Comfort/Sport)? Does the transmission fluid need changing? How many miles has the vehicle done?
Find out at what speed it usually occurs at and try and go through that speed in manual mode.

[mekondelta]

Different tread depths front to rear causing the xdrive to get confused as you're dumping that torque?

[elise2000]

E-bmw said:

Are there any associated noises that may indicate a DMF issue?

It’s an auto

[elise2000]

FlyingPanda said:

Funny enough, I had a conversation with a good Indy specialist that asked me if I’d ever had this (ie: the symptoms you describe) because he’d spotted that I had non-approved tyres on. I said that this all sounded like a bit of tyre marketing snake oil, but he mentioned that the x-drive with a staggered set up (like on a 335d) can get really fussy about even a tiny mismatch and the star-marked tyres are the only way of being sure you’re OK.

I still dismissed it as I have no such issues (Vredenstein Ultrac Vortis) but this just made me think as you mentioned new tyres. Is this when it started?

Tyres are ps4. Had issue before changing

[SteBrown91]

Could be a bad map?

[elise2000]

SteBrown91 said:

Could be a bad map?

Is that something that could happen suddenly when it’s never been a problem before?

[E-bmw]

elise2000 said:

FlyingPanda said:

Funny enough, I had a conversation with a good Indy specialist that asked me if I’d ever had this (ie: the symptoms you describe) because he’d spotted that I had non-approved tyres on. I said that this all sounded like a bit of tyre marketing snake oil, but he mentioned that the x-drive with a staggered set up (like on a 335d) can get really fussy about even a tiny mismatch and the star-marked tyres are the only way of being sure you’re OK.

I still dismissed it as I have no such issues (Vredenstein Ultrac Vortis) but this just made me think as you mentioned new tyres. Is this when it started?

Tyres are ps4. Had issue before changing

And what were they before?

[elise2000]

E-bmw said:

elise2000 said:

FlyingPanda said:

Funny enough, I had a conversation with a good Indy specialist that asked me if I’d ever had this (ie: the symptoms you describe) because he’d spotted that I had non-approved tyres on. I said that this all sounded like a bit of tyre marketing snake oil, but he mentioned that the x-drive with a staggered set up (like on a 335d) can get really fussy about even a tiny mismatch and the star-marked tyres are the only way of being sure you’re OK.

I still dismissed it as I have no such issues (Vredenstein Ultrac Vortis) but this just made me think as you mentioned new tyres. Is this when it started?

Tyres are ps4. Had issue before changing

And what were they before?

Also ps4

[SteBrown91]

elise2000 said:

Is that something that could happen suddenly when it’s never been a problem before?

If its pushing components too hard it could be causing odd behaviour due to components deteriorating but I would expect codes to be logged.