Ok I have a Cold air intake I unplug the sensor while the engine is on slight change in the engine. I plug the sensor back in very slowly the engine stalls. When I plug the sensor in quickly the engine doesn't stall. So what are the symptoms of a bad maf or is this normal? 2001 Audi A4 1.8t quattro.

 

Does the engine run noticeably worse with the MAF plugged in? That's the usual test - if it runs better when it's disconnected, it shows the MAF is bad. Signs are usually rough idle, misfires, bad mpg, and a whole host of potential codes (any combination of this).