Thanks to my cobb AP, the process of elimination, and this thread I was able to fix my P0021.
If you can change the timing belt you can easily do this r&r ( with a hefty 10mm Allen wrench and a cheater bar).
I was getting no avcs advance so this thread led me to the avcs plunger sticking. I did not see any debris in mine, but there was some sludge in the corners. I worked the plunger til it moved nicely and then reassembled with some oil inside. I have not seen torque specs for the 6 bolts, but to remove them took 12 NM for the smaller diameter and 20 NM for the larger, so that's what I used for assembly. Pep Boys had a 1/4" drive T30 tamper proof torx plus (5 lobes) for $5. The bolts aren't tamper proof, just 5 lobed. Part number 9687.
I tried to prime it by turning the engine over with no fuel, but it still took a mile before it started working.
Thanks Underdog, you made this doable for me!