Hi all

ran into this issue on my M40i recently where I was trying to go into the next lane when my car was almost stationary, but not stopped.

Despite pressing the accelerator fairly firmly, there was a scary delay when the engine revved but the car barely moved forward.

Is this likely to be the transmission just taking its time to drop gears? Should it not already have been at pretty low gear as the car was almost stopped? Or does it stay in a high gear (for economy) until the car has complete stopped?

It was scary and takes away some of my confidence in the car's response. Maybe using the paddle to downshift might have helped...

thanks

satz wrote

Hi all

ran into this issue on my M40i recently where I was trying to go into the next lane when my car was almost stationary, but not stopped.

Despite pressing the accelerator fairly firmly, there was a scary delay when the engine revved but the car barely moved forward.

Is this likely to be the transmission just taking its time to drop gears? Should it not already have been at pretty low gear as the car was almost stopped? Or does it stay in a high gear (for economy) until the car has complete stopped?

It was scary and takes away some of my confidence in the car's response. Maybe using the paddle to downshift might have helped...

thanks

Crikey....I'd be back to the dealer before experiencing that again...

30i does it too. Your explanation is perfect, it’s like the transmission isn’t ready to downshift or the logic doesn’t prepare it for the potential of rapid acceleration.
Some people have fumbled around with the traction control, others keep it sport most. I’m somewhere between pushing the shifter to the left for transmission sport mode and just pulling the left paddle shifter. If you pull and hold it the car with shift to the lowest possible gear instantly. Dealer will tell you cars fine…

I've seen this happen a few times when the drive mode is not in Sport+ (or Individual with engine set to sport+). It has something to do with steering angle. It feels like the transmission went to neutral. I can always replicate it when coming from a lane and merging into a highway (or basically into any perpendicular road).

What mode is this in? Do you have the auto start stop on etc?

My response in sport throttle and transmission is near instant at all speeds... sometimes i felt a small hesitation but never anything that was out of the norm.

Sounds like typical turbo lag to me.

Having owned numerous turbo-equipped vehicles, I have learned that you cannot mash the pedal and expect instantaneous response. Excepting my wife's Volvo S-60 R, which also has a supercharger; that vehicle accelerates immediately.

But anyway, if I know I am going to need to accelerate from stop or near-stop, I goose the throttle a bit. Then the response is much quicker.

As someone who drives manual mode 99% of the time, I believe if you're slowing down but do not stop completely, the car does not shift down to 1st gear. I noticed the car will only auto-downshift to 1st gear once it stops completely otherwise it stays in 2nd gear.

So assuming you're in comfort mode, 2nd gear, and some turbo lag due to almost being at stand still, yeah I could see how you could experience quite a delay when accelerating.

Although it's kinda weird to hear the engine rev hard but the car doesn't accelerate. Did the engine rev a lot harder once the turbo kicked in?

This sounds a lot like what people complain about on the RDX/MDX. A software issue that prevents power application immediately after a turn. It is meant to protect the drivetrain I believe, but is poorly calibrated. There are some funny videos about it, one by savage penguin/goose if I recall.

ASAP wrote

What mode is this in? Do you have the auto start stop on etc?

My response in sport throttle and transmission is near instant at all speeds... sometimes i felt a small hesitation but never anything that was out of the norm.

Mine was in sport mode, with auto start stop disabled.