BimmerFest BMW Forum banner
1 - 20 of 38 Posts

· Registered
Joined
·
405 Posts
Discussion Starter · #1 ·
I've been finding that the car has exhibited sluggish acceleration lately...

If I punch the gas pedal on the highway, it's as if it "chokes" a bit first before starting to pick up power.

I was thinking maybe I'm not driving in the proper range of the power band...i.e. most power/torque at higher RPM's?

Or possibly fuel injectors?

Anyone else experience this and have some suggestions?

2008 E63 with 62km (~40k miles) and 6-speed MT.
 

· Super Moderator
Joined
·
10,297 Posts
I've been finding that the car has exhibited sluggish acceleration lately...

If I punch the gas pedal on the highway, it's as if it "chokes" a bit first before starting to pick up power.

I was thinking maybe I'm not driving in the proper range of the power band...i.e. most power/torque at higher RPM's?

Or possibly fuel injectors?

Anyone else experience this and have some suggestions?

2008 E63 with 62km (~40k miles) and 6-speed MT.
It sounds like you might be running in Safe Mode, possibly a problem with the Vanos system, or MAP sensor. Safe Mode is not the correct term, but I can't think of what I want to say.
 

· Registered
Joined
·
405 Posts
Discussion Starter · #4 ·
sport mode or regular?
Thanks BamaGoose. It's happening in regular/non-sport mode.

I rarely use sport mode. I think it only affects the suspension and the pedal response, right? But this doesn't seem to be a pedal response issue...

I remember it being quite different from when I first got the car about 8 months ago. It had much better responsiveness then - even in non-sport mode.
 

· Registered
Joined
·
405 Posts
Discussion Starter · #5 · (Edited)
It sounds like you might be running in Safe Mode, possibly a problem with the Vanos system, or MAP sensor. Safe Mode is not the correct term, but I can't think of what I want to say.
Thanks HerbP! What's safe mode?? I only recognize that term from MS Windows starting up! hahaha

Are there some quick checks I can do myself to determine safe mode/vanos/map sensor?

I have Carly diagnostics and it doesn't show any errors...I would think vanos/map would trigger an error, no?
 

· Super Moderator
Joined
·
10,297 Posts
The Vanos system will go into a Failsafe mode, or a default limp mode to keep the car driveable. There will be a loss of power, but the engine will get you around. Unplug your MAP sensor or any components related to the Vanos system, & you will notice the difference. I am not sure if Carly will let you test the Vanos system for problems, like ISTA will?
 

· Registered
E28, E64
Joined
·
673 Posts
I've been finding that the car has exhibited sluggish acceleration lately...

If I punch the gas pedal on the highway, it's as if it "chokes" a bit first before starting to pick up power.

I was thinking maybe I'm not driving in the proper range of the power band...i.e. most power/torque at higher RPM's?

Or possibly fuel injectors?

Anyone else experience this and have some suggestions?

2008 E63 with 62km (~40k miles) and 6-speed MT.
1. It's mostly like the back two barrels opened too quickly or a bit like turbo lag. Sport mode will cure some of that. It won't fix blipping the throttle for down shifts.

2. Torque peaks at 3400 per the manual. Truck-like curve. HP determines your top end.

3. I did a major service at 90K and ran a bottle Techron fuel system cleaner thru afterwards just in case and no difference in either mode.

This is the BMW drive by wire world. I have to slow my foot down in wifey's 240SX.
 

· Registered
Joined
·
405 Posts
Discussion Starter · #9 ·
Hey guys, sorry for the delay and thanks to everyone for the replies! I wasn't getting notifications of replies to this thread...

@HerbP - I'm going to check out the MAP sensor and maybe just replace it as it isn't too expensive I believe. It doesn't seem like limp-mode, as the power is definitely there - just a lag at initial throttle press.

@myles4gone - I had the CCV valves replaced a few months ago, so I don't think there are any rips, but maybe they installed them poorly?

@zod - yes, it totally feels like turbo-lag! I also just did the BMW fuel cleaner/Techron and didn't notice anything yet. My biggest concern is that I don't remember this "lag" when I first got the car about 8 months ago. But maybe I wasn't paying enough attention.

I don't mind it necessarily and am not racing anyone...lol...I'm just concerned if it's a bigger issue that's going to crop up at some point.

I checked Carly and no errors other than the usual suspects.
 

· Registered
E28, E64
Joined
·
673 Posts
i bought this car 14 months ago. It did the bog and surge so much in standard mode that SWMBO asked what was wrong with my car. Sport mode is better, but you can get some herky jerky in first gear. I'm just looking to drive sporty and it's my first drive by wire car.

There's no realistic way to get anymore grunt out of the car, but fixing the throttle response seems attractive. Forum members seem to like this:
https://www.youtube.com/watch?v=Bbn7hI1kpA0

Thread notification around here has a strange algorithm.
 

· Registered
Joined
·
405 Posts
Discussion Starter · #11 ·
Thanks zod!

I think the Sport button should have the same effect as a Sprint Booster, no?

They both increase the pedal response from what I understand and the sprint booster is for cars that don't have the Sport button installed.

i bought this car 14 months ago. It did the bog and surge so much in standard mode that SWMBO asked what was wrong with my car. Sport mode is better, but you can get some herky jerky in first gear. I'm just looking to drive sporty and it's my first drive by wire car.

There's no realistic way to get anymore grunt out of the car, but fixing the throttle response seems attractive. Forum members seem to like this:
https://www.youtube.com/watch?v=Bbn7hI1kpA0

Thread notification around here has a strange algorithm.
 

· Registered
Joined
·
2,723 Posts
Thanks zod!

I think the Sport button should have the same effect as a Sprint Booster, no?

They both increase the pedal response from what I understand and the sprint booster is for cars that don't have the Sport button installed.
No the Sprint Booster remaps the gas pedal. It's a very different experience than sport mode. I have a friend that has it on his M6 and it may not be any faster with it on, but it sure feels like it.
:bling:
 

· Super Moderator
Joined
·
10,297 Posts
Hey guys, sorry for the delay and thanks to everyone for the replies! I wasn't getting notifications of replies to this thread...

@HerbP - I'm going to check out the MAP sensor and maybe just replace it as it isn't too expensive I believe. It doesn't seem like limp-mode, as the power is definitely there - just a lag at initial throttle press.

@myles4gone - I had the CCV valves replaced a few months ago, so I don't think there are any rips, but maybe they installed them poorly?

@zod - yes, it totally feels like turbo-lag! I also just did the BMW fuel cleaner/Techron and didn't notice anything yet. My biggest concern is that I don't remember this "lag" when I first got the car about 8 months ago. But maybe I wasn't paying enough attention.

I don't mind it necessarily and am not racing anyone...lol...I'm just concerned if it's a bigger issue that's going to crop up at some point.

I checked Carly and no errors other than the usual suspects.
If you have access to a smoke tester, run a smoke test on the engine. It is starting to sound more of a vacuum leak issue somewhere. Check your email address to make sure it is set up properly for replies to the thread. I have seen mine act up lately also.
 

· Registered
Joined
·
405 Posts
Discussion Starter · #15 ·
Hey guys! Just an update:

Replaced the 4 Vanos solenoids today and believe the problem is solved! Low end pickup is much better and the lag/lurch/hesitation seems to be gone.

I read some posts that just replacing the o-rings might be the trick, but my mechanic said the solenoids are a wear item that probably needs replacing after certain mileage anyway, so I did them. Not cheap - about $600 from the stealership - even after my large discount.

Hope it helps someone else with the issue!
 

· Registered
E28, E64
Joined
·
673 Posts
Now you have me thinking. I'm at 98K mi. and throttle response in sport mode seems more sluggish than a few weeks ago. Torque seems to be down and it's also been very hot here: 90-95F. Any particular way to diagnose this?
 

· Super Moderator
Joined
·
10,297 Posts
Most of the time oil varnish builds up inside the solenoids. You usually can use WD-40 or brake cleaner to clean the solenoids. If the smaller o-ring has a slight groove in it, oil can bypass the solenoid path, & change the timing.
 

· Registered
Joined
·
405 Posts
Discussion Starter · #18 ·
Now you have me thinking. I'm at 98K mi. and throttle response in sport mode seems more sluggish than a few weeks ago. Torque seems to be down and it's also been very hot here: 90-95F. Any particular way to diagnose this?
I read on some other forums that it's a maintenance item, so maybe at 98k miles it's worth changing them anyways (if they were never changed)

My car has 65k (kilometers), and they were obviously already acting up as I noticed a huge difference today! The old ones *looked* to be fine though...so I guess it's hard to tell if they're bad by just looking at them.

If cash is tight, just do the 2 o-rings on each one as a start.
 
1 - 20 of 38 Posts
Top