[vye90n52]

I got a 2011 n52 bmw 328xi. Recently i noticed when im in d and my foot on the brake the car start intermittently shake every 5 minute or so and the rpm jump from 600 down to 500 and back to 600. I changed all the spark plugs and coils and it didnt fix it. Any ideas as to what cause this ? Thank you in advance

[BashShah]

when your tank is near empty, then go to Chevon and put half or full tank of their best with Techron. It will clean your injectors and ports since your car is naturally aspirated.

let us know what happens after finishing the tank.
Run it at high rpm for a bit for, high spirted driving will help.

[vye90n52]

turn out i have a big vaccuum leak. Along with that one of the coil i put in is faulty but not to the point where it would throw a code. I ran the car at high load at low rpm and managed to make it throw a misfite on cyl 6- switch the coil out and the car is running fine now !