I think a kogel is a bearing but I don't know which one. Is this the wheel bearing? Have you replaced the wheel bearing yourself and failed to adjust it properly?
I think the problem with your power steering is an air leak? This means that the engine power will be very low at idle and the extra load caused by the power steering pump is making the engine stall. If this is true, then the problem is not the power steering but an air leak on the engine. You need to check the rubber air hoses for signs of cracking or splitting.
Sorry I can't be more helpful.