[SpencerC_6MT]

I recently picked up my Estoril Blue (obviously 6MT) pre-lci M240i, and I love the car. I only have one thing that's bothering me, that being rev-hang. Before purchasing the car, I took a look online to see if M240i owners had any issues with rev-hang. From what I read, it was an issue with N20/B46 cars, but N55/B58 didn't have the issue.

In my personal experience though, I've noticed the RPM's will stay right around redline when I floor the gas and go for the next gear. Very weirdly, I don't feel the issue in 1-2 shifts, but I hear it in 2-3 and haven't hit redline in 3rd (yet). Has anyone else encountered the issue with their 6-cylinder cars?

[230iZTR]

I don't have the source in front of me, but I'm pretty sure its the ECU sensing that there's unburned fuel in the chamber when you came off the gas suddenly, so it lets the revs hang to burn it off rather than causing an emissions problem or a pressure spike that could damage the engine.

It irritated the hell out of me during a test drive so I went with the ZF8 instead.

[gosi]

It’s an emissions thing and all new engines should have it. There is rev hang with the ZF8 as well as the car will continue to accelerate for a short while after you let off the gas, if you are in normal mode. If in sport/sport+/dsc off the car makes a brap noise and closes the throttle suddenly and so no additional acceleration. Have you tried that with your manual?

Otherwise only a ECU flash could solve this.

[SpencerC_6MT]

Originally Posted by gosi

If in sport/sport+/dsc off the car makes a brap noise and closes the throttle suddenly and so no additional acceleration. Have you tried that with your manual?

I daily drive in DSC OFF (not smart, I know, but it's the only way to disable auto rev-matching) so it's always in that mode when I pin the throttle.

I think an ECU tune is my best route. I can eliminate the rev-hang, turn off the auto rev-matching, and maybe get a bit more power, probably around 380 to put it on-par with an M340i.