BMW - bumpy ride!

JMR

Firstly, apologies for my ignorance on such matters, I know next to nothing about cars!
I have a 2014 BMW 520D Estate.
Recently, on startup, and it may be my imagination but it seems worse on cold mornings, when I go over the slightest bump, the suspension seems to over-react and it feels like I'm driving over the worst rutted track imaginable (which I'm not).
You'd nearly bang your head on the roof, a cup of coffee would definitely spill for instance.
It seems to calm down pretty quickly and only occurs on startup

Anybody got any idea if this is a big issue / something to worry about??

Thanks

GustavoFring

Is the back of the car lower in the mornings? There's airbags on the back suspension which can give trouble.

JMR

GustavoFring wrote: »

Is the back of the car lower in the mornings? There's airbags on the back suspension which can give trouble.

Not that I've noticed, would it be quite noticeably lower?

tphase

Almost certainly one or both of the rear suspension airbags is leaking.
The compressor eventually pressurises the bags which is why you only have a bumpy ride after startup. You can alleviate this by allowing a few minutes after you start the engine to give the compressor time to pump them up however if you don't sort out the airbags, you risk damage to the compressor as it's doing a lot more work than is normal
A pair of replacement airbags can be got online for around €330, compressor is about €370

https://aerosus.net/bmw/filter/fitting_models/5/p_construction_year/2014.html?pf=1&focus=list

JMR

tphase wrote: »

Almost certainly one or both of the rear suspension airbags is leaking.
The compressor eventually pressurises the bags which is why you only have a bumpy ride after startup. You can alleviate this by allowing a few minutes after you start the engine to give the compressor time to pump them up however if you don't sort out the airbags, you risk damage to the compressor as it's doing a lot more work than is normal
A pair of replacement airbags can be got online for around €330, compressor is about €370

https://aerosus.net/bmw/filter/fitting_models/5/p_construction_year/2014.html?pf=1&focus=list

Thanks for that, much appreciated.

Is it a big job to fit the new airbags?
Not that I'd try myself, just trying to guage what I'm looking at for a mechanic to install?

kirving

GustavoFring wrote: »

Is the back of the car lower in the mornings? There's airbags on the back suspension which can give trouble.

You might not notice it immediately, as the anti-roll bar can cause the opposite side air-bag to hold the car up and level enough.

I had similar on an an E-Class. It was so slight that my mechanic only noticed the compressor running for longer than it should after the car was off for an extended period and restarted.

It should be quick enough to fit, 1hr labour max if it's just an airbag. Not surprised a 2014 would be showing it now, they're effectively a wear part.