Two problems related to radiator hose have been reported for the 1999 Ford Expedition. The most recently reported issues are listed below.
Heater hose leaks at the back of the firewall, drips down on top of spark plugs and shorts out spark plug & wire. Also see smoke from oil burning from same back area. No oil on the ground. Also, smell antifreeze & oil through vents after heater hose was repaired.
This is reported because of the common nature of this problem and the expense of repair. This is a faulty design which routes an engine coolant hose such that when the hose connection leaks, it drips onto the #4 coil pack and shorts it out. This defect has been carried over through at least three model years (97,98& 99). The cost of my repair was approx. $400. This is not normal wear nor is it a random component failure. I suspect Ford knows about the problem. As a high volume production company, their quality department has surely flagged this defect through some form of failure trend analysis effort.