[ashmailusa]

Hello everyone,
A new happy member here, yet already in need of advise
535Xi ~70k miles
I noticed my car shaking on startup till RPMs go a little down. Not horribly but noticeable enough.
Also, I get around 17mpg with 60% highway/40% town with smooth throttle.
I changed spark plugs and air filter just recently. Didn't really help much. I was trying to look through error codes with BMWaicoder - nothing really related to the issue. Will try to install Rheingold and give it another try.

Previous owner of the car mentioned he had some hesitation upon acceleration. Dealership was supposed to replace vanos. But they ended up just cleaning it since the previous owner didn't have time to wait for a new part.

Do you guys have any recommendations/ideas?
I have a little bit of extended drivetrain warranty left, really want to fix the issue. I wonder if I can insist on replacing of vanos since they never did that at first time?

[Paladinraye]

Originally Posted by ashmailusa

Hello everyone,
A new happy member here, yet already in need of advise
535Xi ~70k miles
I noticed my car shaking on startup till RPMs go a little down. Not horribly but noticeable enough.
Also, I get around 17mpg with 60% highway/40% town with smooth throttle.
I changed spark plugs and air filter just recently. Didn't really help much. I was trying to look through error codes with BMWaicoder - nothing really related to the issue. Will try to install Rheingold and give it another try.

Previous owner of the car mentioned he had some hesitation upon acceleration. Dealership was supposed to replace vanos. But they ended up just cleaning it since the previous owner didn't have time to wait for a new part.

Do you guys have any recommendations/ideas?
I have a little bit of extended drivetrain warranty left, really want to fix the issue. I wonder if I can insist on replacing of vanos since they never did that at first time?

Cleaned the vanos?

"This part needs to be replaced, but I'll just clean it and save a ton of $$$ for a temp fix, then pawn it off on the next guy!"

[mashpotato]

You mean vanos solenoids and sensors. Yeah they can be cleaned or replaced. Do you have any codes from ista scan?

A note is to use good oil and proper change interval.

[ashmailusa]

You mean vanos solenoids and sensors. Yeah they can be cleaned or replaced. Do you have any codes from ista scan?

Yes, that what I meant. Still working on ista scan
Generic scanning software didn't show any error codes so far

[ashmailusa]

Well...I decided to diagnose my car at dealership. No faulty codes upon them...
Oh well...I guess I will try to clean MAF sensor

[burro_blasta]

What about coils? 70k might be about time anyways if original coils are still on. As a new owner, new coils will give you the sanity of knowing where your new mileage "baseline" starts on the coils.

Please verify this, but I recall seeing rough idle can point to coils - even though it sounds like it's only your cold start not your normal idle.

17mpg isn't abysmal, but agree you can hope for better.

[Bmwdoubles_]

If you have an x drive there is a known issue with hesitation on launch. It's on this board somewhere.

Rough idle could be many things. Dirty MAF, unmetered air entering the system after MAF, spark plugs and coils, 02 sensors, vacuum leak, vanos cleaning like you mentioned. Try resetting adaptions.

17 mpg also sounds like you have a tune on your car. Have it flashed to stock.

[burro_blasta]

+1 on the xdrive hesitation on launch. When I startup, I need to wait until after the cold start and my revs die down before I drive off, or else I sputter and even stalled once.

On resetting adaptations, just a word of caution there - I don't have any more knowledge than seeing it mentioned occasionally and this article - but wanted to share:

https://www.xhpflashtool.com/blog/adaptions/

"So, with that knowledge, what is it good for to reset adaptions regularly? Simple answer: For nothing. In rare cases, on transmissions with already very high positive adaptions, this can even lead to a situation, where your transmission will refuse to shift and you basically have to rebuild it, before it will work again. And that is the reason, why adaptions do not get reset by the dealer on service work. There is no reasons for it, unless hardware on the transmission has been changed."

[ashmailusa]

Originally Posted by burro_blasta

What about coils? 70k might be about time anyways if original coils are still on.

Appreciate your input!
I would expect misfire being more evident and constant in this case. Am I wrong?

Originally Posted by Bmwdoubles_

If you have an x drive there is a known issue with hesitation on launch. It's on this board somewhere.

Rough idle could be many things. Dirty MAF, unmetered air entering the system after MAF, spark plugs and coils, 02 sensors, vacuum leak, vanos cleaning like you mentioned. Try resetting adaptions.

I was trying to find a thread about xdrive hesitation issue - no luck. What are you guys talking about?

Also, adaption reset - meaning adaption of the transmission?

[burro_blasta]

Originally Posted by ashmailusa

Appreciate your input!
I would expect misfire being more evident and constant in this case. Am I wrong?

I was trying to find a thread about xdrive hesitation issue - no luck. What are you guys talking about?

Also, adaption reset - meaning adaption of the transmission?

Good question...when I've had misfires on this car, the only time they've shown up is when I'm really beating the piss out of the car, redlining over and over again ya know. If you run it hard and don't get any misfire codes then maybe that's not the problem

[Bmwdoubles_]

Originally Posted by ashmailusa

Appreciate your input!
I would expect misfire being more evident and constant in this case. Am I wrong?

I was trying to find a thread about xdrive hesitation issue - no luck. What are you guys talking about?

Also, adaption reset - meaning adaption of the transmission?

https://f10.5post.com/forums/showthr...949&page=2

There's a ton on different bimmer models search for "BMW xdrive hesitation"