Please tell me the issue I experienced this morning is normal, but preventable somehow. When I got off work this morning I started my truck (96 psd); it started right up, let her warm up for about thirty seconds and took off.I made it about a hundred yards when the motor became unresponsive and verrry sluggish, it also sounded like only two of the cylinders were firing. The truck wouldn't go over 10mph even if I floored it; made it another two hundred yards and it died. Then when I tried to start it up it was "hard starting" (it would crank for about 10seconds before firing up, then the motor would die as soon as it had started. I tried this a few times with no success, so I let it sit a few minutes while I looked under the hood (couldn't see anything obviously wrong). The next time I started it I floored the gas right away and after about two minutes of acting like it was gonna die again the idle smoothed out. I let it warm up for five minutes and then it seemed to run normal. It was about 45 degrees out this morning and I didn't have the block heater plugged in(should it be). All help is greatly appreciated, sorry the post is so long!