2000 Audi A4 1.8T, 107k miles. Ran the diagnostic. Comes up as incorrect airflow. What is this? I know it's not the Air-Fuel meter, because i just replaced that 2 months ago. I cleared this code and it came on a few days later again. How easy of a fix? And price estimate? I've had trouble starting the car like 6 times since last week. Assume because of this. Thanks