I've been having an intermittent hesitation problem with my S6 for about the last month or so. MIL was not on but I decided to see if any codes were present. I wrote them down but didn't write the full code. 1st code - 00561 mixture adaption range below spec. 2nd code - 00544 max air charge exceeded. 3rd code - 00537 lambda sensor. 4th code - 00513 engine speed sensor no signal. I'm going to school for automotive technology so I ran a few tests. I know I need a new rpm sensor definitely. As for the hesitation, its intermittent so it leads me away from coil packs or POS, but I did check them and evertyhing seemed fine. It only happens when i reach about 7lbs of boost mainly in 3rd, 4th or 5th gear but has happened in 1st and 2nd. Any help would be appreciated. Thanks in advance.

Will

this

I got a quote from my boss (i work at a garage)for $156 for a new one from a dealership. But i found a few places online that sell 2 different sensor. One was for $165 and one was for $99.

but they do have specific part numbers so make sure your getting the right one.