97 f150 wont start

my 97 f150 4x4 4.6 v8, wont start, ive had the baterry tested, replaced the starter and tested the relay, what else could it be???

One common recommendation here from the experts is when it looks like someone is throwing parts at a vehicle, which is what it looks like here, that it will be cheaper to find a qualified mechanic who knows how to troubleshoot the problem. On this URL is a place called something like Mechanix Files, with recommendations for good mechanics. There are on many cars all sorts of wires to go bad, fusible links from the battery, bad keyed switch; etc. With a manual, Haynes from Autozone or other parts store is fine, it is possible with some thought to eliminate these things yourself. Otherwise, you need someone who knows what he is doing. Sorry.

thank you, i might have to do that, but i realy want to do this at home, i just re-checked the ground on the starter, its good yet still nothing, somebody help me out!

Define “won’t start” - i.e. what exactly happens when you turn the key?