Increased Turbo-Lag with new software confirmed!

[RPM90]

Originally Posted by maxnix

These two sentences make no sense when taken together. But maybe the whole thread does not?

Is it lag or tip in hesitation or something else?

That's a good question, cause it's possible that we are all not using the same terminology, or explaining the same condition.

In my case, which is in other posts, actual turbo "lag" from a standstill has not increased. Take off or launch feels the same.

What I have is poor throttle response at speed at higher rpm, which is where the turbo's are already spooled and should give near instant boost.
This too could be called "turbo lag", but the turbos haven't changed and they did just fine before the update.

I think that BMW tweaked the DBW throttle to give a slower "tip in".
So, even though I may be fully depressing the throttle pedal, it's the ECU that is really controlling the actual throttle servo. With software you can make the actual throttle respond in many different ways in relation to the pedal.

If that's not it, then maybe they tweaked the wastegates, or DV.
It might be that the WG is being opened slightly venting off boost for a second then slowly closing to allow boost to build.
I think it's the DBW, as it would be easier to tweak that to slow things down.

It would be good to know what BMW did, or didn't do.
If they didn't fiddle with anything, then maybe something is wrong.
But, modern tech shops LOVE their computers, and if there is no code, then there is "no problem found".

[SixBanger]

Today Im now on my 3rd pump. Yesterday I had a long talk with my Service Manager and in conclusion he said that the 2nd pump placed in my car back in february was an older version and that I should upgrade to the newer one made in March. So I made an appointment today and bitched about intermittent long cranks and turbo lag. So today I got my way and they installed the new "current" pump. It was pouring rain on my way home from the dealership and couldnt really get on it to tell if anything has changed. However, I do notice that the turbo lag is suppressed and that it feels better to me. So, tomorrow on my way to work or home from work Ill get on it and tell you what I think overall.
Myles

[HondaGoneRogue]

Originally Posted by RPM90

What I have is poor throttle response at speed at higher rpm, which is where the turbo's are already spooled and should give near instant boost.

+1 I am experiencing the same thing. Noticibly more pronounced after the latest update. (The one where the pump primes on unlock). I got that done early May.

[HondaGoneRogue]

Originally Posted by PC Valkyrie

With this "lag" that people are experiencing since getting their software updated, at what rpm do you feel the turbos are really working?............in other words, what rpm should you stay above to not feel the "lag"?

That's just it, there is no magic RPM. The turbos don't stay spooled for long at all anywhere in the midrange. They used to just go from almost any point and indeed was a big selling point for me. I even tout the ultra-low rpm point of full boost/torque to friends and potential customers.



Post update however, it seems like there is a clutch slip almost. You hear the motor rev but the surge of torque doesn't come on until a second later. This over exagerates the application of the throttle (to me and any passenger). It is not smooth and definitely not what I would expect to be an acceptable driving dynamic in a BMW.



One of the greatest impressions I got during my first test drive was that it felt naturally aspirated. You can certainly tell it is turboed now.