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Light Throttle Shake????

8K views 30 replies 16 participants last post by  Fred G 
#1 ·
All,
I am having issues when applying light throttle (acceleration), the car shakes, especially in gears 3-5, even when traveling 30-50 mph...I have a 09 with 48 K miles, 750LI.

There's no smooth power coming from the engine, when I apply full throttle, car responds much better, but I still feel a little bit of shaking, I feel it's masked by the higher throttle and the shaking is still, yet I can't feel it.

1. Have you noticed these symptoms with your car?
2. What can it be? Torque Convertor? Trans? I just had the CCP completed with Timing chain replacement.

Any help is appreciated!
 
#2 · (Edited)
Sounds like an air or vacuum leak to me. Also could be bad gas.
 
#4 ·
I have noticed this also. I am hoping the injector replacement will fix it but I suspect it is the way the transmission is programed. It feels like the car is lugging down between 1000-1800 rpm under light acceleration because it goes away as the rpm gets in the 2000 and above range. The reason I think it is just the way the transmission is programed is because the 320 loaner I have been driving for the last two weeks while I wait for my CCP to be done does the exact same thing. I will report back when I get my 750 back post CCP.
 
#12 ·
Makes sense, and exactly, after 2k RPM the issue goes away, would pedalbox be a good fix for this issue? I hate jumpy acceleration though. Please keep me updated if you find anything else, really really annoying.
 
#5 ·
Yes mine does the same thing in normal mode. It disappears when you go to manual mode (downshifts as soon as you go to manual) or sport mode because the transmission holds the gear longer forcing the rpm higher. It is only noticeable when the engine is cold. goes away or is substantially reduced as the engine warms up.
 
#6 ·
Could be CCP has gone wrong and timing chain replaced - WOW!
 
#8 ·
I had this same exact issue before I dropped it off for CCP and it was one of the first things I wanted to test once I got it back, mine is completely gone and smooth now after the CCP.
 
#18 ·
Post CCP (everything but timing chain and battery) the car still does this. It may be a little better but if so only very slightly, it's probably in my head.

As I posted earlier I beilieve this is just the way the transmission is programmed. Just to be clear, I am not talking about a shake that would make coffe spill or anything; only a subtle vibration until the RPMs come up to the 2k range. Way back when I drove a manual transmission if I shifted too early to a higher gear the car would behave exactly the way mine does. I think the BMW engineers did this to up the MPG, and the issue does go away in sport mode.
 
#20 ·
Post CCP (everything but timing chain and battery) the car still does this. It may be a little better but if so only very slightly, it's probably in my head.

As I posted earlier I beilieve this is just the way the transmission is programmed. Just to be clear, I am not talking about a shake that would make coffe spill or anything; only a subtle vibration until the RPMs come up to the 2k range. Way back when I drove a manual transmission if I shifted too early to a higher gear the car would behave exactly the way mine does. I think the BMW engineers did this to up the MPG, and the issue does go away in sport mode.
It's not in your head dude, it IS slightly better, but just slightly, give it some time.
 
#19 ·
We had our N63 back for one day before it had to be returned "the new fuel line was not attached properly and leaking heavily". Our performance was better than ever, but our N63 was running terribly before it went in so most anything would have been a massive improvement. What I noticed was the slightest hesitation in short succession until the RPM's picked up. I noticed it as I was coasting up to a red light that was in the process of turning green. It was not necessary to come to a complete stop as I was coasting and my foot was off the gas. As I pushed the accelerator to move forward from coasting I could feel the slightest shaking from the driver position. I repeated the process and asked if my wife could notice the shaking. She did not notice the hesitation from the passenger seat. I will check to see if I am still having the shake once I get my N63 powered 2010 550 GT back.
 
#21 ·
Got my car back, trans replaced, 99% better!

It was the trans..good luck to the rest of you who have this issue, I see BMW releasing another CCP
 
#28 ·
I am having pretty much the same issue with my 2010 with 82.5K miles. I feel a light shake when accelerating between 20-50 mph and the RPM are between 1k and 1.7k. I am also experiencing a hard shift between 2-1. It happens only when slowing down to a complete stop. It shifts smoothly between 1-2 & 2-1 while stopped and there are no other odd noises coming from the drivetrain.

I don't know if these two issues are connected. I have read up on the 2-1 hard shift issue and it seems like it can be the Flex Disc/Guibo. This seemed to be the issue on the previous 7s, E65/E66. Let me know what you guys think. It does not bother me enough right now, so I may wait until the next oil change to address the problem, but would love to know what I am in for $$$ wise.
 
#30 · (Edited)
Update after 1.5 years:
1. CCP complete in Feb 2015 including timing chain
2. Transmission replaced in March, again in April
3. Injectors replaced again in April (3 of them)
4. Carbon clean up *8K*, I paid 3K out of pocket (summer 15)
5. Spark Plugs and other related tune up items replaced around winter, issue continues
6. Valve seals replaced in 04/16, 12K (warranty covered)
7. Battery replaced
8. Alternator and High pressure fuel pump replaced, 06/16

Shaking continues...

the light throttle shaking has nothing to do with any of the above items except maybe #1...BMW doesn't know what they are doing, so they are finding work for themselves. Don't pay out of pocket for ANY of these expenses as they are not related to this problem!

I am going to get a BMW NA Tech come out to check out the issue, it's really painful. Total cost over last 1.5 years? 70K+.
 
#31 ·
I'm having this same problem now on my 2011 750, it drives fine for about and hour or so, then when I slowed down and then speed back up it would hesitate then get stuck in gear and the transmission malfunction light came on, when I shut the car off and let it reset for a little while it would drive fine again, I also get that heard shift but mine seems to be between 2 & 3 or 3 & 4 BMW warranty is over, about to get a warranty with AAA!
 
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