Help Required Please!!

[MikeYQM]

Help please!

My 2013 M3 DCT has stock axle back, AFe intake and Alpine Stage 2 tune. Plugs and O2 sensors were replaced in the last 5000km.

Last night I removed the stock (with test pipes) X-Pipe and installed a Bimmerworld Resonated Catless X-Pipe. I used new donut gaskets and tightened everything down snug.

I'm getting a very pronounced rattle under acceleration. When cruising, when trying very mild acceleration (slowly rolling on 30-50% throttle... almost lugging the engine) it sounds like a coffee can full of marbles. If I roll on more throttle, it gets louder and the engine starts to hesitate. It takes a prolonged time to downshift when in D mode, even in D4 or D5.

At times, it will not go over 3000RPM no matter the throttle input and feels like a strong misfire with hesitation and jerks.

Once it eventually downshifts or RPM do get over 4000rpm it's absolutely fine. Better than fine... it's amazing. But when it's doing this, it drives and sounds like a very loud piece of crap.

Does anyone have any suggestions? I drove home from work last night, all was well. I installed the X-Pipe and now this. There are no codes being thrown.

I'm relatively new to the M3 but my suspicions are:

1. The tune is not agreeing with the mod and needs to be updated.
2. The adaptations need to adjust to the change.
3. What I'm hearing is enhanced rasp from the catless pipe and I'm over thinking it and holding the car in lugging range longer while trying to assess it.

Thanks!

In this video you can hear the rattle:

In this video, you can hear the rattle come on at 2500 rpm with about 50% throttle in D4, 7th gear at 120km/h and then quickly disappear at 3500 rom

[SYT_Shadow]

There's long thread of many alpine tune users and the forward-placed xpipe users

Audioslave686

[MikeYQM]

Originally Posted by SYT_Shadow

There's long thread of many alpine tune users and the forward-placed xpipe users

Audioslave686

Found the post, no solution there though...

[SYT_Shadow]

Originally Posted by MikeYQM

Found the post, no solution there though...

I know.

What I've seen as a workaround is to shift manually and not let it go under 3k.

[MikeYQM]

Ugh. I HATE workarounds. The car should be able to drive how I tell it to, not the other way around. Are there any other tunes that have good success with these pipes?

[SYT_Shadow]

I agree the car should work properly

I know in the long thread there are people contacting him and getting different revisions. Apparently the stock software doesn't do this so some have loaded that.

Cheers