5.8 egr help cont.
from my earlier post i pulled the egr valve assy and started the truck, the manifold line is not blocked. valve pulls freely with vaccum and is also not restricted. hooked every thing back up and started the truck, chugs and surges until i unplug the egr vaccum line then purrs? but, the mil light is on! how do i fix this? i'm i following symptoms and not the cause? like maybe the thermac sys is bad? any help from you ford guys will be greatly appreciated... if it makes a diff. this trouble is with a 1988 F150 2wd