[A535_Mcfly]

My 2016 BMW 535i has recently been starting up funny every morning. I already tried changing the battery already, not sure what else I should do. I changed the spark plugs about a year ago. Now when I start it up in the mornings, the RPMs are dropping to low, it almost seems like it is not gonna start up but it ends up bouncing back up and balancing itself out. I never had this problem before, so I know something is off. The car is at about 90k miles. I dont know why or what to do at this point. Let me know if you guys got any suggestions please and thanks!

file:///C:/Users/andre/OneDrive/Desktop/WhatsApp%20Video%202023-10-04%20at%2012.33.33_248ba0b0.mp4

[StradaRedlands]

Have you checked for any stored fault codes?

[A535_Mcfly]

Yea nothings coming up, its so weird

[ezaircon4jc]

Originally Posted by A535_Mcfly

My 2016 BMW 535i has recently been starting up funny every morning...

Tell it to be more serious!

[ChiltiCoatl89]

How low on the RPMs does it drop? does it fluctuate and is it only during initial start up?

[ChiltiCoatl89]

How long does that fluctuation occur?

[ChiltiCoatl89]

Try the Chevron Complete Fuel System cleaner, you also messaged in a different thread about your issue. Be sure you are using very good 93 Octane fuel (I used to live in Jacksonville, FL) I only put Shell/Vpower or Chevron/Techron, Try that first because it is too easy to think it is something very complex where it can be something so simple. which can lead to big money replacements that may not be necessary at all!

[clown123]

The decrease in RPM may be affected by temperature, which is also a normal situation

[ctcarbonari]

I've read quite a few posts on this issue and have yet to see a "definitive" cause. N55 Engine @ Cold Start (not warm) - RPMs dip to ~500 then bump up to 1.8k - 2k then back to ~ 1k and eventually settle.

I've had this issue start about 18 months ago (@~65k miles). Initially would occur 1 out of 50 cold starts. Now it occurs about 1 out of 3. Also, will sometimes go for a few days without doing it at all, then a run of a few days will do it each time. Sometimes the dip & correction is 500 rpm to 2k, a lot of times it's a bit less (800 rpm to 1500 rpm).

I've read everything from carbon buildup, spark plug / coils, MAF sensor, vacuum leak, & leaking fuel injector to be the cause but have yet to read a post on a definitive "fix".

I always use Chevron 92 octane and run Techron Fuel Cleaner about 500 miles before each 5k oil change. Both my plugs & coils have about 17k miles on them.
No codes. I'm wondering if it's due to a leaky fuel injector (my OA results from past couple changes have been on the high side for fuel concentration)

I'd love to read some solid feedback from others who have successfully addressed this issue or have some good insights on a method for diagnosis.

[SWFLf10]

I had a similar issue on a BMW with the N52 engine during cold starts when I swapped the Vanos solenoids on accident. Could be dirty/old Vanos solenoids? Just a thought.