[Buckeyes]

Op, any updates on the cold start rattle? Did you find a fix. I have the same noise on a cold start that last for about 3-5 minutes.

[Bimmer28312]

Never got an official answer but kept hearing its normal noise from an N55. To make you feel at ease I've since gone FBO w/jb4 running 4-6 gallons of e85 over a year now. No issues at all atm

[Buckeyes]

Thanks for the update

[ChrisMcP05]

Different issue but on the topic of sounds - I get an engine bay shake (only sometimes) when I turn the car on and it's a cold start. It also can shake - make a rattle (but deeper sounding rattle, almost as if the clutch is being slipped too late and is struggling) when just starting moving - going slow start letting the clutch out. I've opened the hood - still got the noise, removed the engine bay cover - still heard the noise, but it doesn't sound like something mechanical. I'm not sure if motor mounts on these cars go after a while or struggle - even though the car is used very lightly / rarely beaten on. The only thing else I could think is the intake shaking or rubbing when cold - possibly some movement. There's also a ton of snow on the ground so not sure if it's a factor - but I did notice the noise right after I put the intake on.

[LMT0286]

When i installed my injen cai i never had a stall or that rattle. My guess is u missed a bolt and its causing someghing to rattle. Just a guess though especially if it started after you installed it

[LMT0286]

Nvm jjs saw this is like 2 hears old lol

[Dark_Knight_335]

You have an N55- you should have no waste-gate issues.

That was an issue mostly in the earlier years of N54 cars.

I get that cascading whoosh sound every once in a while, and yes, I've been told that this is due to how our twin scrolling turbo works.

Also apparently there is this blow off valve-like mechanism we have that the N54 does not- further exacerbating these unusual turbo sounds.

Install a BMS intake and see how much more you hear it LOL

[JETmn]

No, that certainly wasn't normal. There is another clanking noise besides the injectors. It sounds fairly big and hollow, exhaust rattling maybe?

[13335iagl]

i just bought a 2013 335i and it has the same rattling noise. the car came with aftermarket intake pipe and ignition coils. the car has 96.6k on the odometer without any check engine lights. i got it off a small dealer. oil levels are good temp. levels ok as well got a 'reduction in brightness due to excess temperature' and a tune was also found in the car. also metal shavings in the oil.

upon starting the car a rattling noise is heard from the engine also when i accelerate. its loudest when I am idling on a red light. but im not getting any lights on the dash. any thoughts and advice would be greatly appreciated.

i tried to upload vidoes but no luck.

[yupetc]

I had rattle noises during idle, too. Sounds like a loose timing chain slap; but sound goes away revving beyond 900 rpms. So I took these steps:

1) Took the belt off and ran the motor to eliminate any sound coming from idler pulley or tensioner. rattle sound during idle is still there.
2) On top of valvecover, checked injector hold-down bracket to make sure injectors are sprung, no bounce, all good.
3) Took the valve cover off to inspect the timing chain from up top, things are taught, no loose chains. Timing chain tensioner also gets inspected, no issues.
4) Drained the engine oil, remove the oil level sensor, insert a camera scope to inspect the inside of oil pan for debris. Nothing found.
5) Bust open the vacuum pump cover and the oil pump tensioner access port. Inspect the tension on the oil pump chain, --> Got a little bit of "play". My N55 has the Plunger-style tensioner, and what I found is a stuck tensioner because I couldn't even push the plunger back by articulating the tensioner guide arm. This is where my problem is. I have a stuck tensioner, and the oil pump chain must have seen a little slack so it's slapping around during idle. I also found the oil pump sprocket gear to have a little bit of scoring near the teeth too. So this sprocket gear has some wear to it. On plastic tensioner guide arm which is being pushed by the tensioner plunger, on the chain-gliding side, it's got some erratic pattern of sunk groove on that guide rail.

So... I decided to replace the entire oil pump and chain assembly, and this requires removal of the crank shaft bolt which is impossible for me to do while the motor is on the car. Further long story short, took the motor out of the car, took it apart, sure enough the tensioner for the oil pump chain is in a stuck position. Was able to use a vice to press it in and it's now loose again and good to go. Of course this won't be used again and will be replaced by an OEM unit.

Not that this is common to find, but for those of you who are hearing the clattering-like rattle noises, do suspect timing chain or oil pump chain for those are the only two components which will rattle and slap if either tensioner or guide rail craps out.