2007 4.8 X5 Lunging Problems

[ard]

Originally Posted by X5ists

Will the software update will solve the problem? Talked the dealer yesterday, needs to bring it in for diagnostic and update if there is an update for my transmission for $219.....they need the X for the whole day.

"trans not releasing- an issue with the lock up torque converter, or associated sensors actuators." is it an expensive fix??

Probably worth $219 to maybe fix it.... but anything inside the transmission is $$$$$$ with a BMW dealer.

[BMWjason]

FYI, The jerking is caused from using low octane fuel. This engine is nearly 11:1 compression. The knock sensors are very sensitive. This engine needs octane. I have run this motor on 30% E85 and regular unleaded equivalent 95 octane. It will wow you. I only recommend E85 in dry desert climates. The minimum octane for this motor is 91, and that is still lacking.