[xavier335i]

I just got my first 335i couple weeks ago came with dinan stage 2 car drove fine 400 miles home but now when i turn it on the service engine soon light comes on if i drive it normal it drives fine but when i try to get on it pass 5k rpm the light comes on and car start misfiring for about a min then goes away the valve where clean about 3 weeks ago but idk how old the plugs and coils anyone know what it could be and how i can read the service engine soon code ??? Thanks guys i know theres a search bottom i try to look but no luck

[WilliamS]

if its under load, my first aim would be plugs/coils. There are circumstances that could be a leaking or faulty injector but thats much rarer than plugs/coils.

Do the misfires come from a specific cylinder? If so move the coils around and see if the misfire follows. If it doesnt, then plugs are a good start.

[xavier335i]

How can i check what cylinder is misfiring same the light goes away in about a min idk to check wish one is misfiring and thanks for the response