BimmerFest BMW Forum banner

1 - 15 of 15 Posts

·
Registered
Joined
·
337 Posts
Discussion Starter #3
It feels normal. So you think it's a voltage issue? My first guess was a vacuum leak but I get no codes
 

·
Guibo killer
Joined
·
83 Posts
well if the motor itself is not erratic, you'd have to go with voltage. my needle dances like that, but I have the dreadful n54 and know it is gonna suck hard for me because my engine is erratic
 

·
Registered
Joined
·
1,134 Posts
Try an OBDII bluetooth plugin and an app like Carly or Torque, even the free versions should be able to display RPM live. If that says the engine speed is steady, and you can hear the engine idling steady, then it's probably a gauge issue. I've never stared at mine that closely, it might be a "they all do that" thing.
 

·
Registered
Joined
·
337 Posts
Discussion Starter #7
I have noticed that when I check on Carly the engine speed does change. It goes up and down. Any ideas on that might be the problem?
 

·
Guibo killer
Joined
·
83 Posts
Look at voltage and the air/fuel ratio, that will say bad MAF probably. There are an incredible number of vacuum leaks are possible too. Get some break cleaner and start spraying around the hoses and the boot to the MAF and see if the idle bogs.
 

·
Registered
Joined
·
337 Posts
Discussion Starter #11
I will get some break cleaner and check. On Carly I don't know which parameters to choose exactly as there are so many on there. I wish I knew exactly which ones to choose on the app
 

·
Registered
Joined
·
337 Posts
Discussion Starter #14
It's roughly between 500-600 rpm. But very rarely it has also done it to me while driving, no specific range on rmp
 

·
Registered
Joined
·
825 Posts
That's a pretty good swing. Somethings wrong. Have you cleaned the idle controls valve for the idle issue? The throttle body assembly, MAS assy and idle controls valve should be cleaned with throttle body cleaner and not brake cleaner. CRC makes a product that will do a good job on all 3 referenced and at 120k not a bad idea even if you didn't have a problem.
 
1 - 15 of 15 Posts
Top