I have five codes 16885 Vehicle Speed Sensor Implausible signal, 16684 Random/multiple cylinder misfire, 16690 Cylinder 6 misfire, 16684 Random Multiple Misfire- Intermittent, 16690 Cylinder 6 Misfire-Intermittent.

I started having a random intermittent stuttering sort of feeling in the right front a few weeks ago. I figured it was the ABS brakes going out. Then this week I had the AC running and when I went to take off from a light it had no power and the stuttering was very pronounced. I switched off the ac and it went away immediatly. Then it happened in a less pronounced way later in the day. I was thinking the AC clutch might be going. The next day it ran fine until I was on a steep hill and it happened and got worse as I climbed. The AC was off. So I parked it and yesterday I put the computer on it and got the codes above.
The codes came up just as written. The problem is definitley Intermittent.
I've searched on here and the only thing I haven't done is the coil packs which I am hesitant to do. $400!Zoinks! (99 Pas 2.8V6) I changed the plugs (Bosch), wires (aftermarket), MAF (reman), and a the breather hose (I used an off the shelf hose and connected the ends not the OEM one) a couple months ago. I'm hoping for a bad MAF which I think I can get replaced for free. I got it at AutohausAZ online. I'm going top try looking thru the VAG-COM diagnostic procedures to see if it has any repair suggestions.
Any comments and suggestions from those who've had this kind of probblem please. Also if you know how to test a MAF that might help. Oh should I clean the throttle body? I'm not even sure how to. Oh yea can that Speed Sensor cause the misfires? it ran really well right up until it didn't. :-}
One more thing I replaced the check valve I think the N18 or something because of a problem after refueling of it not wanting to run until it was started 4-5 times.