If a ywing using an unhinged astromech takes the damaged engine crit is the turn 3 red or green. Thanks guys.

Red. The negative always trumps the positive.

Red, as stated in the FAQ. When two conflicting cards modify the same thing maneuver, the negative effect takes precedence.

EDIT:

EDIT: Corrected, thanks Forgottenlore

Red. The negative always trumps the positive.

Red, as stated in the FAQ. When two conflicting cards modify the same thing, the negative effect takes precedence.

That isn't really correct. That rule only applies to MANEUVERS (so it DOES apply in this case but), that doesn't mean it is supposed to apply to anything else. The actual entry in the FAQ is

Q: If two or more game effects that change the difficulty of a maneuver conflict, which effect takes priority?

A: An effect that increases the difficulty of a maneuver takes priority over an effect that decreases the difficulty. For example, if a ship equipped with R2 Astromech is dealt the Damaged Engine Damage card, all of the ship’s turn maneuvers are treated as red maneuvers, including the 1-speed and 2-speed turn maneuvers.

Red, as stated in the FAQ. When two conflicting cards modify the same thing maneuver, the negative effect takes precedence.

EDIT:

EDIT: Corrected, thanks Forgottenlore

Doh! I hit quote instead of edit there, didn't mean to post again, NEWB.