Join Date: Aug 2005
Location: Not Quite Philadelphia, PA
Thicker oil will give you the romps once you get it turned over. During cranking it will be thicker and cause longer crank times.
Did you measure the resistance of all 8 glow plugs? If everything else on the truck is good, just a couple of those being bad will make the truck hard to start or even prevent it from starting.
1999.5 F250 creeping up on 400k.
Check your wiring harness: Chaffed wiring at driver's valve cover.
Keep everyone (and yourself) updated:7.3 mileage and repair thread
If you insist on throwing parts at your truck to fix the problem, go big--don't forget the driver's side frame rail.
If your ICP connector has oil in it, change it. Don't argue, just change it. Don't check other things first, just change it.