my 99 super duty has had some electrical issues for the past few years that comes and goes. 1 is the feed to the headlight switch for parking la,ps and dash illum. goes out and found power at fuse in pdc but no power under dash where wire is coming thru firewall connector. Now last year I hooked up trailer wiring under pdc to rear of truck. I flipped over pdc and wired truck. After I returned pdc, truck cranked slow, no wait to start lamp, and of course no start. I messed around and tested power to ecm connector and found nothing. Shortly after, the truck started. Now , I know you will say it is the pdc that is bad, but under fuse panel showed power. Was wondering if anybody had issues with the firewall connectors doing this.( previous winter I lost power to accel. pedal also). Also want to ask again about a performance concern. my truck has new glow plugs, controller and starts fine when cold or warm but always smokes on start up. never uses any oil, but also seems to be under powered compared to two customer trucks I have, 1 being a 99 f450 dump and 2 a 2000 rollback with steel bed.They seem to have a lot more snot, and they both have high mileage like mine 182k. Not to bombard you with issues, just trying to resolve these issues before I give up and sell it for reliability concerns. thank you