Help! RPM dip on startup

cedaj · 12-17-2019, 09:27 PM

Linked is a video of a cold start on my 328i. The rpms fluctuate ONLY when the car is cold. Doesn't happen while driving or anything. Has this happened to anyone?

Mods:
ER intercooler
Bm3 stage 2
Injen evo intake
VRSF downpipe

RMachuca3d · 12-17-2019, 11:31 PM

Cold start off or on? Sounds like you have it off?

cedaj · 12-17-2019, 11:53 PM

Yeah, I turned cold start off cause of the catless downpipe

andino · 12-18-2019, 12:21 AM

Could be your intake or the lack of cold start. How long before you set off after you start your car?

cedaj · 12-18-2019, 07:56 AM

Quote:

Originally Posted by andino

Could be your intake or the lack of cold start. How long before you set off after you start your car?

It hasn't had that issue before, the car starts right up and then the rpm dips for a second and then it idles normally. Doesn't do it when I try again after starting it, only when it's cold and hasn't been started in hours

MilanF30 · 12-18-2019, 09:21 AM

This doesn't look serious to me, there's no obvious change in engine sound, you can only see that rpm needle is moving a bit down, and for a fraction of a second... I mean, it is a cold start, so engine cannot run perfectly yet.

You can try to revert cold start delete, and see if it happens again...

12-17-2019, 09:27 PM	#1
cedaj Private 12 Rep 73 Posts Drives: F80 Join Date: Feb 2018 Location: New York iTrader: (0)	Help! RPM dip on startup Linked is a video of a cold start on my 328i. The rpms fluctuate ONLY when the car is cold. Doesn't happen while driving or anything. Has this happened to anyone? Mods: ER intercooler Bm3 stage 2 Injen evo intake VRSF downpipe
	Appreciate 0 Tweet Quote

12-17-2019, 11:31 PM	#2
RMachuca3d Captain 724 Rep 943 Posts Drives: F30 328i Msport Join Date: Aug 2018 Location: WA iTrader: (2) Garage List 2015 BMW 328i Mspor ... [0.00]	Cold start off or on? Sounds like you have it off?
	Appreciate 0 Quote

12-17-2019, 11:53 PM	#3
cedaj Private 12 Rep 73 Posts Drives: F80 Join Date: Feb 2018 Location: New York iTrader: (0)	Yeah, I turned cold start off cause of the catless downpipe
	Appreciate 0 Quote

12-18-2019, 12:21 AM	#4
andino Captain 480 Rep 681 Posts Drives: F31 328i xdrive Join Date: Jan 2019 Location: norcal iTrader: (2)	Could be your intake or the lack of cold start. How long before you set off after you start your car? __________________ 2016 328ix F31 - SOLD! 2006 997.1 C4S
	Appreciate 0 Quote

12-18-2019, 09:21 AM	#6
MilanF30 Private First Class 48 Rep 108 Posts Drives: BMW F30 328i Join Date: Sep 2014 Location: Serbia iTrader: (0)	This doesn't look serious to me, there's no obvious change in engine sound, you can only see that rpm needle is moving a bit down, and for a fraction of a second... I mean, it is a cold start, so engine cannot run perfectly yet. You can try to revert cold start delete, and see if it happens again...
	Appreciate 0 Quote