My 2008 528i was lurching forward when at a stop (only when the engine was cold).

During a BMW repair shop investigation they determined that my transmission had a slow leak . They said this was the reason for the cold engine forward lurching of the car.

I had the transmission leak repaired and new fluid put into the tranny. My car is still lurching forward when it is cold. In addition a full inspection and a few more minor things repaired.

What could this be coming from?

If I am at a cold stop with the brake pressed down and instead of releasing the brake, I put the car in Park, then back into Drive there is no lurching.

I have had the brakes checked a couple of times as well...and they seem fine. Everything is pointing to a transmission problem.

Any ideas?

 

so the car lurches forward when you let off the brake? do the rpms jump too?

 

Ditto - do the rpm's jump?
I had a Merc blow the Idle Air Control Valve - similar experience as what you're having. Though I'm suspecting you might be having the dreaded 5 series surge.. that's mechatronics. There are solenoid rebuild kits available but can't comment much more than that.

 

what was causing the leak to begin with Was it the mechatronics seal sleeve or the other gasket in the tranny for the driveshaft (forgive my ignorance of its name..output flange seal or something maybe).

 

I too have this lurching only when the car's not warmed up enough. After a little drive its normal. I probably need a tune up. My car just hit 80k miles.

 

I would need more details but from what the OP described here it Sounds like the valve body. BUT as a rule make sure you have reset your adaptions. You really should make sure the software is up to date first before thinking this is a bigger issue than it is and also make sure that it has the correct fluid and it's filled correctly. Over filling can cause issues as well.