Ok I dropped the pan to replace the solenoid. checked valve plunger and it's moving freely (but i guess that could change when it's hot).
rick427 - i push in on the plunger till it bottoms out, then release - and it doesn't snap right back out but probably takes 1 full second to fully come back out. is this normal? a stiffer spring would shoot it back out faster, but i know it's moving some fluid around so maybe it shouldn't shoot back out as fast as i'm thinking.