In MArch 2014 I had change my MAF on my audi s4 b5.....since 2 week I have a P0102 code thats mean MAF low input!! Whats mean ? I hope my maf doesnt need to be change.....I change it last year for a Brand new BOSCH maf.....my s4 is stage2 chip (j-fonz)...

want to know what I can check to see if its my maf or another parts ..... and i want to know if I can mesure the MAF directly not on the car with ohmeter?