[DaveH28]

So Ive had the 440i for 3 years now, its being VT'd and going back on Monday.

So my inner child came out and fancied doing a swansong launch control,

Now, I have felt like the 440i wasn't pulling like it used to for a couple of months, but no lights or warnings, plus I was driving the replacement around (335d) so was thinking it was just the difference in torque.

Anyway, today I did the launch control and expected to be thrown back in my seat with the wheel spin and fishtailing like it has done on the very few occasions I have done it before, last time was probably 18 months ago.

Today, it just felt like it was held back up until about 20mph and then the surge hit, this feel also ties up with how the car has felt in normal driving for the last couple of months. Its fully serviced, second one was done in October last year.

Doesn't worry me too much as its going back, but just wondering if anyone else had felt anything like this on their x40i's if I didn't know any better id say it feels like something to do with the transmission. but no faults, Ive diagnosed on Rheingold too.

[RobUK]

Mine's getting on for 3½ yrs old now and has covered 33K miles, but I've never experienced the sluggishness you describe (either before or after the MPPSK). Must confess I tried LC a few times once it had done about 4K miles but have never done it since.

[DaveH28]

Originally Posted by RobUK

Mine's getting on for 3½ yrs old now and has covered 33K miles, but I've never experienced the sluggishness you describe (either before or after the MPPSK). Must confess I tried LC a few times once it had done about 4K miles but have never done it since.

It's only been the last couple of months,
It's done 43000 miles now, but apart from this feel, it's never missed a beat..

As I say I thought was the off the mark torque difference after driving the 335,
But the LC definitely wasn't right today

[Goneinsixtyseconds]

Mine's always been like that in launch control. Find it underwhelming so don't bother. Like yours, I'm at 43,000 miles and doesn't feel sluggish in any other way.

I was told the first couple of times you use launch it allows the wheels to spin as you've described, but then it learns and the nanny systems that aren't ever really disconnected stop it doing it.

[DaveH28]

Originally Posted by Goneinsixtyseconds

Mine's always been like that in launch control. Find it underwhelming so don't bother. Like yours, I'm at 43,000 miles and doesn't feel sluggish in any other way.

I was told the first couple of times you use launch it allows the wheels to spin as you've described, but then it learns and the nanny systems that aren't ever really disconnected stop it doing it.

It's the off the mark and everyday driving where it has felt just that bit laboured, enough for me to notice..

Didn't know that about the launch control... I bet I haven't done it more perhaps half a dozen times in 3 years..
Most of which were after run in... as a bit of a 0-60 test.

Will be sad to see it go, but the 335 has a story, which I'll share when sorted.. then hopefully can tide me over until the m340i is year old... trying to avoid another pcp.

[blueislander]

hang on, how do you make launch control happen?! I am only 2k miles in so still being a bit careful!

[DaveH28]

Originally Posted by blueislander

hang on, how do you make launch control happen?! I am only 2k miles in so still being a bit careful!

Haha..
Stick to the left, put it in sport+ or traction off..

Press brake pedal hard while then pressing accelerator all the way, should come up with a flag on dash and launch control activated message,

Let brake off and hold on

[blueislander]

Originally Posted by DaveH28

Haha..
Stick to the left, put it in sport+ or traction off..

Press brake pedal hard while then pressing accelerator all the way, should come up with a flag on dash and launch control activated message,

Let brake off and hold on

... And that's Sunday morning sorted.

Thanks!

[RobUK]

Originally Posted by DaveH28

Haha..
Stick to the left, put it in sport+ or traction off..

Press brake pedal hard while then pressing accelerator all the way, should come up with a flag on dash and launch control activated message,

Let brake off and hold on

I always had visions of the car leaping off down the road leaving a trail of oil and engine shrapnel in its wake. I think I have some sort of mechanical sympathy (probably unjustified) and so never remember LC is there when I'm in the car

[DaveH28]

Originally Posted by RobUK

I always had visions of the car leaping off down the road leaving a trail of oil and engine shrapnel in its wake. I think I have some sort of mechanical sympathy (probably unjustified) and so never remember LC is there when I'm in the car

Haha.. I know what you mean, I think it's all done within tolerances, as long as you don't repeatedly do it... all is fine.. I did it a couple of times when it had done about 3000 miles.. then maybe twice for a giggle in the last couple of years
Then yesterday..

[Goneinsixtyseconds]

Originally Posted by RobUK

I always had visions of the car leaping off down the road leaving a trail of oil and engine shrapnel in its wake. I think I have some sort of mechanical sympathy (probably unjustified) and so never remember LC is there when I'm in the car

BMW have made it pointless in the 40i anyway. Launch control holds at a teeny bit over 2,000 revs and when you release there is an initial small push and then a pause as the revs rise to give you more torque and power.

My old Audi A6 with the same gearbox, but a biturbo Diesel engine, held at just over 3,000 revs. That went off like a shot, no pause anywhere.

3000 revs with an engine that only revved to 5,000. 2,000 in a car that revs to 7,000 is no where near enough, you're not in the proper power band when you "launch". Exciting it isn't.

Apparently in an M3 you can manually adjust the revs launch holds at to make it a bit more exciting. But the same process doesn't work on the 40i.