2020 p400. 12k or so miles. I did an interim change of oil at the dealer at 10,000 miles.

Ever since I’ve had it, on a cold start, after it revs up a little higher for about 10 or 15 seconds and settles down into its normal rpm, there’s a rattling noise that sounds quite like the bad timing chains on an old 5.0 V8 supercharged. It kind of rattles as the idle settles down and then the rattle goes away after about five or 10 seconds.

Anyone else notice this? it seems a bit of an odd noise.

 

I would say yes but kind of mild though in my case. I didn't think too much of it but it's a p300. Again maybe fuel? Lots of admonishments from my service advisor about a specific brand of fuel to avoid.

 

I had a very similar issue with my ‘23 90 P400 from the moment I drove it off of the lot. It only rattled in a certain rpm range (1-3k) and went away once it warmed up. Took it in and the dealer replaced the muffler and haven’t heard it since.

 

I have a 2021 P400, it has a clatter at low RPMs on a cold start - a little like our old 2011 BMW X5 35d but quieter. The faint clatter goes away after it comes up to temp. No drivability issues and I haven’t had the recall taken care of yet.