My father-in-law has a 1998 4.0 SOHC Explorer, that starts right up, but then cut-offs instantly. If you start the car and hit the ga, it will catch. Just to eliminate the basics, I chsnged the plugs, wires, air-filter and will be doing the fuel filter this week. The car has 45K on it, what do think could be wrong??

PS-I did reset the computer, also whre is the PCV on this car??

Sounds like your IAC (Idle Air Control) motor, it controls idle. It's located on your intake manifold.

Welcome to the site CJ.

I second Jason's suggestion. Do a search for IAC and you'll find lots of posts about it and suggestions how to clean or replace.