Im Playing with friends on a Mod pack Server. But Immersive Engineering dont work like it should. Only a few Items are listed on Just Enough Items, but in Creative Mode i can use the missing items but i cant craft them in Survival mode. Could it be a Problem with the Modpack?

Sounds a lot like a problem with the modpack.
Use the issue template that you so rudely ignored and provide more info, or else we won't be able to help you.

Well, I guess the issue is closed ¯_(ツ)_/¯