I have an 01 EX 7.3, and I keep setting a p0678 code. My programer (Edge juice w/attitude, and Edge evolution) is telling me that it is a code for the #8 glow plug. It seems to trip this code when I really jump on it. which I find weird because the glow plugs shouldnt even be on then (correct?) The truck es running and starting fine even in the bitter cold. Any Ideas? and will this code put the truck into limp mode and effect MPG's? Im really tired of reseting. Also any Ideas on how to fix it?