Installed Burger Tuning PBX in 2010 x3 xdrive
 

Seeing as BMW wouldn't do anything about the hesitation from a standstill & when accelerating from low speeds I decided to install a tuner. The Burger Tuning PBX fixed things up just fine. It wasn't too bad to install (was a bit freaked out pulling the ECM out) & definitely takes longer than the manual if you've never done one. The default "lag fix" program took care of the hesitation. Recommend it to anyone who's frustrated with the low speed drivability.

What year and engine? What on earth is a PBX?

It's a 2010, 3.0 engine. The PBX "Powerbox" connects to a handful of wires in series to the ECM. I'm not sure of its full scope but I know it does remap the signal from the throttle & reduces the lag from acceleration when not in sport mode.

Thanks - interesting, is this a common problem on all x3s?

Seems to be a common complaint.

hrm, i haven't noticed it.... can someone describe the hesitation?

Our hesitation was most noticeable when moving at idle or just above say up to 15 mph. You jump on the gas (as in crossing a busy intersection or merging) & the vehicle doesn't respond at all for 1 second or so. It's just enough delay in busy urban traffic to put you in harms way if you aren't careful, that and it's really annoying.

Mine does that too, unless I drive in SD mode. When in SD mode it is always ready to go.

Normal D mode is more relaxed and has a delay. Mercedes is the same.

Frenchie, I purchased the PBX for my 2007 X3, but the connector colors and wires in their installation guide are different from the X3. How did you figure out how to wire it?