truck turns over but don't start

Thanks for the reply, I checked compression and its all good.Srayed the carb cleaner with the throttle wide open and it wants to fire up but only for a couple of cranks and then it just turns over. It actually starts up about an hour later. It starts on the first crank and idles for about a minute and then dies. Crank it again and idles for about 20 seconds then dies. It wont start after that for another hour or so. Also when I crank it over I'll press on gas pedal all the way down and it wants to start but it doesn't. Just recently replaced the TPS,cleaned the MAF sensor,new wires and plugs and also put new gaskets to the upper intake just in case. Checked all vacuum hoses and connections. Finally after speaking to a mechanic at my nearest FORD dealership that assured me that the fuel pump was bad, I replaced it. NO LUCK. Any ideas?

this is exactly what's happening to my 2001 ford explorer. Did you ever figure out what was happening? Thank you!