User_irl

Hi Guys. i have a question to E60 530diesel drivers. I bought BMW 530d E60 '04. i am worried about acceleration of my car. Acceleration of my car looks like a spring. As if when i press the accelerator pedal the spring is squeezing (speed is growing up very smoothly), and then suddenly explodes (circa after 2000 revs) and abrupt acceleration. is this normal, what do you think? does everybody have the same?
Thanks!

UK 5 Series

Have you by any chance just moved from a petrol to a diesel? If so, that's a characteristic of diesel engines. They have loads of power mid range, but can seem sluggish at very low rpm and run out of puff at high rpm compared to a petrol. You'll soon get used to it and learn to work around it, enjoying the huge torque surges.

If you are an experienced diesel driver, then ignore all of the above. Your car clearly has a problem!

colejl

Yup, sounds perfectly normal. This is lag before the turbo kicks in...

Mine does the 'leap' at just over 2k rpm...

This is where the twin turbo's of the 535d make a difference and the boost is started lower down the rev range and the acceleration is more linear.

User_irl

My previous car was a BMW 530d E39, also Automatic (but 5 speed). And on E39 i did't feel such sluggish at very low rpm. But E60 a lot powerfull after 2k rpm. Acceleration on E39 was more linear. Even from the start after kickdown E60 starts a bit slowly and around 2k rpm suddenly explodes and traction control starts flashing.
I gave the car to the dealler to check the engine and he said with the engine everything is OK. Now I'm thinking maybe there is some problem with gearbox? I did't check the gearbox yet. Or is it a big difference between 530d E39 and 530d E60?
Thanks.

Mike O

What you are describing sounds exactly like my car, also a 530d auto. I think that part of the problem is that in ordinary mode the gearbox sets off from a standing start in 2nd gear and nothing seems to happen until the turbo kicks in. Nowadays I put the gearbox in sport mode to pull out of junctions so I can avoid the problem of pulling slowly out in front of other traffic and then suddenly taking off like a scalded cat!

Hawkwing

As has been commented by others turbo lag is present in the 530d, also in the 535d albeit less intrusive; however bear in mind too that the throttle control is not linear in the 3ltr diesels due to the electronics dictating the application of the throttle in a non linear manner, this according to BMW's responses to my earlier query on throttle response from start and slow speed pick up; according to what BMW wrote in their letter to me the non linear build up of engine speed is to aid compliance with EU4 regulations (particle emissions) and protecting the transmission from the very high initial torque loading - the most noticeable time for the effect to occur is from start and low speed pick up.

boltoa

I've got a late 2003 E60 530d. It's a manual, and I would say the turbo kicks in around 1800 rpm. It's a characteristic of a turbo car rather than a diesel (if you've ever driven a non-turbo diesel, not that there are many these days, you'll definitely notice the difference). Big-turbo'd petrol cars do exactly the same this - my Evo 6 had pretty much nothing until 3000rpm. Twin-turbo RX7 (see, BMW weren't the first to do it on a petrol car) was better, but still needed about 2300rpm.

You just have to learn to live with it really - it's easier in a manual I suspect, as you can control the revs via gear selection easier.

"Turbo lag" is more generally referred to as time it takes to respin up between gear changes - ie if you're redlining in 3rd and you change to 4th (revs maybe drop down to 3000), it still takes a while for the turbo to get back up to speed, as the suddenly shut throttle during the gear change causes the turbo to stall. Mitigated by dump valve, aka blow-off valve, which allows air to recirculate round the intake system thus avoiding turbo stall. I'm fairly sure the diesels have a recirculating dump valve (could be wrong), but they never stop lag entirely. This is also less of a problem in autos as you don't lift off so much during a gear change.

Anti-lag in a rally car is another beast entirely . Pop pop pop bang.

Andrew

colejl

It could be my imagination but I think it has got 'worse' over the years...? Perhaps I'm just getting sensitive to the characteristics... Our S-Max has much the same 'issues' - If you change too eary the revs drop noticably off-boost and your progress is blunted for a second or two...

I never had an E39 to compare but like it's already been stated BMW had to tinker around with the responses for emission compliance...

mixterk

I have a 535d..lag no way near as bad as you described but still noticable, i cam our of a 330i petrol and i needed to get used to it, the smaller turbo does take a lot of the lag away...all but gone since DMS remap. A collegue with a 530d does comment that his kicks him in the back at about 2k rpm..maybe a remap?

User_irl

I was thinking the same and today i did a remapping. The car now like a bullet!!! A lot better than before, but i still can feel a lag before 2k revs. Before remapping the lag was about 1 second, now 0.5 second.
But after 2k revs - ...
Now I definitely can live with this.