What scan tool are you using; do you have the ability to read the maf data (pid) as you drive or the car idles?
Lately, we seem to be seeing; broken or cracked plastic electrical plugs/connector; going to the maf and the locking clip can be broken, not locking the plug securely. Also, the terminal ends become loose over time and this can result in a intermittent bad connection issue; which can result in a maf related trouble code.
To check this, you can observe live data of your maf; then do a "wiggle test", by wiggling the wires and plug. If you notice the data stream drops out; in relation to your moving things, then this could be a sign you should probably replace your plug and terminal ends to the maf.
You can get new plugs and terminal ends from your local vw dealer or a cheaper, lower quality plug/wire already assembled "pigtail" repair jit is available online from places like amazon or ebay. Here in the states, aftermarket companies; like Dorman and Standard Motor Products, sell these at local auto parts stores, as these plugs commonly get damaged and fail, causing problems.
Get the part number iff the old plug and use that to search online fir a replacement part.
For the higher quality parts; your local vw dealer is probably the better quality with genuine vw parts, most aftermarket brands are being supplied from China and the quality can be lacking. I was getting some maf related codes and found my plug was cracked, the locking tab was broken and i got a new one from my local vw dealer, which fixed the problem.
Fir splicing in new terminal ends; be sure ti use the newer design butt connectors; that have heat shrink tubing and internal sealing adhesive, which seals the connection, stops common problems like moisture ingress related corrosion and increases pull strength as well. Many companies make these now; i've found 3M to make high quality versions and use them on my recent repairs with excellent results.
