[Robs335iproblems]

I have a 2018 340xi that has the same surging problem listed in this post. https://f30.bimmerpost.com/forums/sh....php?t=1541584 Before this started happening, the car was great. Lots of power and took well to the MHD stage 2 tune. But now, it's almost un-drivable. I thought the BMS intake was the issue, but two days after removing it, the issues have returned, so I have no idea what is causing the surging. I have a 2015 435 with the N55, tuned and modded and the car is great with no issues. I have never experienced a car that can't simply accelerate without issues. It only has 28k miles and I'm becoming very frustrated that it's a problem that isn't going to be solvable.

[Skyhigh]

Sounds like you have a problem with your tune, not with the B58 engine itself. Unless you have the same problem using stock software, this post really doesn't belong in this thread…

[Houck1224]

Originally Posted by BMWILUVU

Does the chirpies come after you shut the engine off after a drive?

Mine makes that same noise, any idea what it is? Happens sometimes right after turning the car off, chirps for like 5-9 min then stops

[Robs335iproblems]

My poor drivability issues and surging was related to the intake VANOS actuator. There were no codes or any other apparent issues, outside of the car surging under light acceleration. 29k miles. In old N series engines, the VANOS solenoids were nearly bulletproof, but the actuators on the B58 are a new design and may need attention sooner. Something to keep an eye on.

[gantona]

Originally Posted by E92Vancouver

Timing chains only last the life of the engine if you change the oil regularly. If you don' the chain stretches (actually rollers wear out not actually chain stretch) which wears out the camshaft gears.

It’s a wet timing chain ?!