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Initial acceleration

11K views 42 replies 16 participants last post by  mikeymac 
#1 ·
I just got back from my 2 month Ed and already miss my 650 and I know your going to think I'm crazy but. Has anyone else felt that the first split second of accelation lags? After the rmps get above 3k it's a beast but it just feels like something is missing or I'm I crazy. When I got home and got back into my x-5 which is 5 years old with the 300 hp 4.4. It has that neck snap initial acceleration that I just don't have in my 650 or am I just crazy? Or do I just need to break it in some more.

One more thing has anyone had this one happen. I'm driving for about a hour in at 120-130 mph for about 45 minutes. Car starts stalling like it's not getting enough gas or enough air. pull to the side of the road. Turn off the engine. Thinking great I'm in the middle of spain wonder how roadside works in the middle of no wear in spain. I turn over the car and see if it resets it self and it does. No other problems. Crazy huh?

Thanks for any imput on the 1st section.

Brian
 
#13 ·
How?
 
#6 ·
I just got back from my 2 month Ed and already miss my 650 and I know your going to think I'm crazy but. Has anyone else felt that the first split second of accelation lags? After the rmps get above 3k it's a beast but it just feels like something is missing or I'm I crazy. When I got home and got back into my x-5 which is 5 years old with the 300 hp 4.4. It has that neck snap initial acceleration that I just don't have in my 650 or am I just crazy? Or do I just need to break it in some more.

One more thing has anyone had this one happen. I'm driving for about a hour in at 120-130 mph for about 45 minutes. Car starts stalling like it's not getting enough gas or enough air. pull to the side of the road. Turn off the engine. Thinking great I'm in the middle of spain wonder how roadside works in the middle of no wear in spain. I turn over the car and see if it resets it self and it does. No other problems. Crazy huh?

Thanks for any imput on the 1st section.

Brian
Did you try using Sport Mode. I've finally got around to using it and noticed a big difference with acceleration. I have a 6sp manual though and I've noticed Sport is more responsive than on an automatic.
 
#8 ·
Ha, ha. It's both actually. I definately feel more acceleration aaaaaaannnndd that fuel needle also drops faster. But that low-end pull....wow.
 
#14 ·
put key in ignition, turn to position 2 (just enough so it doesnt start) and for you push start guys... put key in, (do not put foot on brake) press "Start" button

Now you should be in ACC mode. Now put your foot on the accelerator, all the way down, past kick down. (you should hear a slight click, when you got past the kickdown)
Now keep your foot their for about 45secs...

Now, let go of the accel, put foot on brake, start vehicle. Put into D and go for a spin.. you will imediately notice the difference!
 
#15 ·
Thanks:thumbup:
 
#19 ·
I did this procedure this weekend. I think the acceleration may be a little smoother from stop in regular "D", but then again it may be a placebo effect. I've tried playing around with sport mode on and off and again, MAYBE there is a difference; jury is still out, though...
 
#20 ·
its a fact that it makes the acceleration smoother, shifter better... because it puts the tranny into "learning mode" again. Not a "placebo"
 
#25 ·
Okay, the jury has finnished deliberating....the verdict is that there IS a difference in smoothness from a stop and acceleration is more responsive at any speed. Not a HUGE difference, but a difference nonetheless. I have to say, I like it better this way! :thumbup:
 
#29 ·
haha u have no idea... he is cra-zieehhh
 
#31 ·
Has anyone else felt that the first split second of accelation lags? After the rmps get above 3k it's a beast but it just feels like something is missing or I'm I crazy. When I got home and got back into my x-5 which is 5 years old with the 300 hp 4.4. It has that neck snap initial acceleration that I just don't have in my 650 or am I just crazy? Or do I just need to break it in some more.

One more thing has anyone had this one happen. I'm driving for about a hour in at 120-130 mph for about 45 minutes. Car starts stalling like it's not getting enough gas or enough air. pull to the side of the road. Turn off the engine. Thinking great I'm in the middle of spain wonder how roadside works in the middle of no wear in spain. I turn over the car and see if it resets it self and it does. No other problems. Crazy huh?
Brian
Hey Brian, I have been getting the same hesitation as well, it usually happens earlier after I have just started the car and am driving, but today it happened at almost every light and stopsign. I have to push the throttle a little more to get it past the hesitation, and then it jumps out too fast once it tips in. The person next to me then thinks that I am trying to show off, but what do I care? :dunno: I have thought this might be attributable to using 89 octane fuel and ethanol mix fuels, as this happens sporadically. I will mix in a 91 octane tank with every two 89 octane, but I am not sure if this is affecting the hesitation or not as I have not monitored it - but just simply assumed.:)

TS
 
#33 ·
No offense but why would you even bother using 89? When bmw recommends nothing less than 91... Theres obvioslly a very good reason behind using 91, and 89.. such as engine knock, loss of power, lack of mpg and so forth. Hesitation... maybe related. Seems like the civic drivers dont mind using 91+ octane, but bmw 6 series drivers want to using 89- ... haha go figure
 
#32 ·
I just got back from my 2 month Ed and already miss my 650 and I know your going to think I'm crazy but. Has anyone else felt that the first split second of accelation lags? After the rmps get above 3k it's a beast but it just feels like something is missing or I'm I crazy. When I got home and got back into my x-5 which is 5 years old with the 300 hp 4.4. It has that neck snap initial acceleration that I just don't have in my 650 or am I just crazy? Or do I just need to break it in some more.

One more thing has anyone had this one happen. I'm driving for about a hour in at 120-130 mph for about 45 minutes. Car starts stalling like it's not getting enough gas or enough air. pull to the side of the road. Turn off the engine. Thinking great I'm in the middle of spain wonder how roadside works in the middle of no wear in spain. I turn over the car and see if it resets it self and it does. No other problems. Crazy huh?

Thanks for any imput on the 1st section.

Brian
I felt it too and I think I am going to reset the transmission...however, the car is a lot more responsive in the sport mode...I didnt really notice the gas needle :D while I went cruising at 120...lol!

So, this is a weird question...after getting the dealer change my brakes (front and rear) + sensors I got rid of the hissing noise...however, today while I was braking, this was at a speed of 80mph...and changing lanes at the same time I felt as it the front of the car went slight right and then came back straight.. as if the wheels turned right and then got back to the straight position (I did not turn the steering though....)..I felt it was weird....anyone has any thoughts as to what it might be?
 
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