Audi Repair: Audi 4.0 MAss airflow sensor signal low, air flow sensor, mass airflow sensor

Question
Im driving an Audi a4, 2.0 2001 model. Recently, when I reduce speed or stop, it vibrates and switches off. I was told it was a fuel pump but I replaced it and its still doing the same thing. I went for an engine diagnosis and they found 4 faults:
1. EVAP PURGE VALVE - lower limit exceeded.
2. Oxygen (LAMBDA) sensor - Lower limit exceeded
3. CAMSHAFT POSITIONING SENSOR- incorrect correlation
4. INTAKE MANIFOLD VALVE - lower limit exceeded
5. MASS AIRFLOW SENSOR - signal too low
6. OXYGEN (LAMBDA) SENSOR - internal resistance too high.

What might be the problem and whats need to be done?
Thanks  

Answer
hello
Try to disconnect mas air flow sensor and see if idle gets better and stops switch off. If it's starts running OK, replace mas air flow sensor.
From the other faults looks like you need o2 (lambda) sensor,
After replacing o2 and mas air sensors reset faults and recheck for any left after few days.
good luck                        Greg