[Redbmwm33]

I'll start off with a question. Why on IPW cylinder logging with Cobb does cylinder 5 show 90% and all other show 40% or so?


Now for my issue. On cold starts after the car has been sitting 6+ hours I'm getting a metallic pinging sound from the engine bay while the car is idling or while driving anytime I pass around 1,500 RPMS. Once the car warms up, I no longer hear the noise. Car drives perfectly fine and my logs look 100% perfect.

I'm worried it might be something really bad though.

Car is a 2011 335is and this issue has never happened before.

[Redbmwm33]

Bump anyone??

[LaCross]

Take a video. We dont know what you mean by "metallic pinging" and therefor cannot answer your question.

[Redbmwm33]

I guess it's called piston slap. It only occurs when cold and only when RPMS are exactly at 1500 rpm and I let off the gas.. It will stop for the remainder of the day once the car is warmed up.

[LaCross]

Once again, take a video. Kinda sounds like your wastegates. But nobody will ever know because we cant hear it.

[Redbmwm33]

It's not wastegates, it's coming from the driver/mid side of the engine bay.

[RJ_]

Originally Posted by artsoasis

It's not wastegates, it's coming from the driver/mid side of the engine bay.

Sounds a lot like lifter tick to me. Pretty common issue to have on cold start and it really doesn't harm anything.

The hydraulic lash adjusters can be cleaned out to prevent this. Just something to keep in mind if you happen to have the head being worked sometime in the future, otherwise it's not really worth the effort to tear into the head just to clean the lifters.

[Redbmwm33]

It's weird because it only happens when the car is warming up. It honestly sounds like a marble in a can.

[RJ_]

http://www.e90post.com/forums/showthread.php?t=13504

[Redbmwm33]

My noise is completely Different from lifter tick.. It's a lot more pronounced like a knock.