Engine running lean

What is your question?

My car is 325i, 2004. The car didn't pass the emission test. The dealer recommended changing the cyclone separator and the disa valve, both got changed but didn't solve the problem. The problem is when l try to accelerate the car shots down and bunch of lights comes on on the instrument panel including the EML light. I have to shut the engine completely off then restart ithe again. Nobody seems to know what the problem is. Can you help me please. Thank you very much. Two codes. P0171. And P16A7