The N54 powered BMWs respond amazingly well to tuning, but the increased power has caused some owners to experience misfire issues. Trouble shooting and repairing a BMW can seem like a daunting task with things like an advanced electrical system, specialized tools, and intimidating engine covers. But, diagnosing and repairing the typical misfire is fairly straight forward, and COBB Tuning can show you how!
To learn more about the AccessPORT for your BMW, visit COBBtuning.com.
I had this exact problem about 3 weeks after I installed my Cobb. Turned out to be a coilpack. This video would have been awesome to have when I started troubleshooting. Great vid guys, great quality, easy to understand, thanks for doing these!