Car jerks forward from standstill - e90 320i

[Ahbengdriver]

Wonder if anyone has same experience and managed to fix the problem.

This does not happen when car is rolling but only from stand still.
eg at traffic light when you step on the gas as lights turn green.

In the first half to one sec, the car doesnt respond when you put yr foot down
but after that the car seems to 'launch' itself forward, as if the petrol suddenly
goes into the engine.

Whats the likely probelm here?

 

[Red_Bean_Bun]

Re: Car jerks forward from standstill - e90 320i

NIC issue ............

 

[Ahbengdriver]

Re: Car jerks forward from standstill - e90 320i

simi see "NIC"?

 

[Red_Bean_Bun]

Re: Car jerks forward from standstill - e90 320i

Neutral idle control .... Can try coding to resolve issue.

 

[vexxus]

Re: Car jerks forward from standstill - e90 320i

Neutral idle control .... Can try coding to resolve issue.

Bro, decoding NIC don't help leh..

U gotta explain in lay man terms simi is Neutral Idle Control..

 

[MTechnic]

Re: Car jerks forward from standstill - e90 320i

You press the launch button is it...

View attachment 58587

Wonder if anyone has same experience and managed to fix the problem.

This does not happen when car is rolling but only from stand still.
eg at traffic light when you step on the gas as lights turn green.

In the first half to one sec, the car doesnt respond when you put yr foot down
but after that the car seems to 'launch' itself forward, as if the petrol suddenly
goes into the engine.

Whats the likely probelm here?

 

[casper77]

Re: Car jerks forward from standstill - e90 320i

You press the launch button is it...

View attachment 58587

E90 got tis button meh?? which ws fixed de??? pls pm for damage

 

[Red_Bean_Bun]

Re: Car jerks forward from standstill - e90 320i

This is the explanation from BMW -

"The NIC (Neutral Idle Control) feature disengages the torque converter from the transmission when the vehicle is stationary in the Drive position; the service brakes are applied; and the engine is still in the warmed-up phase."

In layman terms - The jerk, lunge or delay comes in when the torque converter re-engages the transmission when moving off.

IMHO - the approach I would personally take - Go with the less risky and cost effective route first - check first if coding helps as is not as risky as flashing the transmission software or jumping straight into costlier hardware replacements.

My personal experience - my ride jerked and lunged forward to the point it hit the kerb while doing a head in parking (I applied the brakes, looked out the window then release brake) and it jerked then lunged forward, after a delay and hit the kerb. That got me going in looking for a solution.

Along the journey, I tried flashing my transmission software with different versions and found that not all releases of transmission software comes with the NIC disabled. So after flashing and if that release defaults to enabled - problem will still be there. So I flashed in the latest release and double checked the config. The flashing is not necessary - but I did it anyway to satisfy my "latest and greatest" obsessions for my own ride.

It does increase the FC very slightly as it does not remove engine load completely during a stop. About 0.1- 0.2 l/100km and again this number is just for my ride since I travel 80-90% city.

FYI - The NIC feature was specifically created to reduce emissions.

 

[ZEEKY]

Re: Car jerks forward from standstill - e90 320i

Feel that NIC only happened in D mode not DS, anyone can confirm?

 

[Red_Bean_Bun]

Re: Car jerks forward from standstill - e90 320i

Feel that NIC only happened in D mode not DS, anyone can confirm?

Yes. 3 conditions for NIC

- D mode
- Brakes applied
- Transmission warmed up

 

[nhc]

Re: Car jerks forward from standstill - e90 320i

Yes. 3 conditions for NIC

- D mode
- Brakes applied
- Transmission warmed up

May I ask which software did you used to flash your transmission ? I tried resetting the transmission adaptation using INPA and it did not help at all.

 

[Red_Bean_Bun]

Re: Car jerks forward from standstill - e90 320i

May I ask which software did you used to flash your transmission ? I tried resetting the transmission adaptation using INPA and it did not help at all.

Inpa is usually missing a bunch of files - tough bunch of scripts to manage.

You tried flashing your transmission ?

 

[Hotspurs]

Re: Car jerks forward from standstill - e90 320i

Damn 'chim' meh!

 

[Ahbengdriver]

Re: Car jerks forward from standstill - e90 320i

checked with a reputable WS and was told it could be the mechatronic unit is faulty.

The hiadee who posted the launch control pic is correct, although my car doesn't have that feature, it behaves as if it has.
This doesn't happen always but happens if after a long hard drive. When you try to drive off from a stop, the gas is applied n the rpm goes up a bit but no gears engaged. Then when the gears do engage after 1 sec, the car jerks forward like its gonna cum. Nabei.

 

[check13]

Re: Car jerks forward from standstill - e90 320i

I totally understand what u r saying becos mine has the same jerking problem. Try many things but still the same albeit slightly better.
Now waiting to collect car as change solenoid! Sweat...

 

[Red_Bean_Bun]

Re: Car jerks forward from standstill - e90 320i

Your GM or ZF gearbox ?

I totally understand what u r saying becos mine has the same jerking problem. Try many things but still the same albeit slightly better.
Now waiting to collect car as change solenoid! Sweat...

 

[check13]

Re: Car jerks forward from standstill - e90 320i

Pre FL so should be ZF? And I think ws changed for me megatronics, not just the solenoids. Half my bill is due to this as I also did a lot of other stuff due to leak water, leak oil, suspension, brake discs etc. Or bark kart now.

 

[Red_Bean_Bun]

Re: Car jerks forward from standstill - e90 320i

It sounds like it's coming back to you as the ultimate driving machine to enjoy again ...... Haha!

Pre FL so should be ZF? And I think ws changed for me megatronics, not just the solenoids. Half my bill is due to this as I also did a lot of other stuff due to leak water, leak oil, suspension, brake discs etc. Or bark kart now.

 

[check13]

Re: Car jerks forward from standstill - e90 320i

I hope so!!! Many pieces of $100 bill fly away...

 

[canuck78]

Car jerks forward from standstill - e90 320i

I totally understand what u r saying becos mine has the same jerking problem. Try many things but still the same albeit slightly better.
Now waiting to collect car as change solenoid! Sweat...

Let us know if changing solenoids solve your jerking problem completely?