Rough idle on startup - BMW Forum

adambomb · 09-07-2010, 07:36 AM

Hello,

I am new to the forums, and i am sure that there are many posts just like mine so hopefully this will be an easy case for you guys. I have a 2000 BMW 323i. Its all stock. Anyway i have had the car for about 2 years and have been troubleshooting this issue along the way. When starting up from a cold start it has a loop idle. I have noticed this more frequently during the colder months of the year. After doing an oil change it helps, but the problem never really goes away. I have replaced all the plugs, wires, coil packs. I have cleaned the MAS and checked most places for vacuum leaks. I replace a few more things over the years and have done the routine maintenance. I have not cleaned the idle control valve and or done anything with the vanos which from my research tells me those may be the source of my issues. I even made a video for you guys to show you the different sounds and idle problems. At the end of the video it shows what it typically does when it starts up. Please note that the issue goes away when i give it a little gas.

YouTube - 20100907000824.wmv

Youngproexec · 09-07-2010, 01:22 PM

Hey welcome to the forums. I have replied to a post like this just a day ago lol, but i'll be more than happy to tell it to you. I had a problem just like this with my bmw e39 528i 99', and by the sounds of it you will need to replace either your ignition coils ( if not done so already) or your intake elbow ( that's connected directly between the throttle body elbow which is connected to the engine and the MAF sensor which is connected to the intake box. Also, do you experience any loss of power at earlier rpm's say from 0-3000? Does the car feel like it's holding back tremendously? these are signs of cylinder misfires in more than one cylinder, and will need a certified technician to run the car's computer management control system through a computer to pull up the codes, in which the computer will read engine misfires, and the respective cylinders. I would firstly double check for vacumm seal leaks, and the intake elbow connection. I'll post a picture of what it'll look like. There are usually tears in the intake elbows which cause that rough idle and exhaust pattern.

Youngproexec · 09-07-2010, 01:30 PM

here's the picture. I also forgot to mention that the IDV- Idle control valve- could be the problem if it has not been changed or cleaned prior to this issue. If you know how to clean it, then you should start with that firstly. If not, I can make you a diy pdf or picture instruction, or provide you with a link shortly. Good Luck.

adambomb · 09-07-2010, 01:33 PM

thanks I will clean and inspect. Ill let you know.