98 chevy blazer fuel pump stop working 2 week ago. whats wrong with it?

Today it started up after just a few cranks. I replaced the pump almost a year ago. Two weeks ago the pump just was not making that whirling sound like its supposed to. I bought another pump because I finally diagnosed it as a fuel pump failure and didn't touch the car. For s**** and giggles when the new plastic pump arrived. I tried to see if it would start and it did. What could be my problem? I tried every troubleshooting tip in the Haynes Repair Manual. Also when its cold outside it takes a while to start.98 chevy blazer fuel pump stop working 2 week ago. whats wrong with it?
did you install the new pump or simply try the old one before replacing?...there are many thing,s that can cause intermittent failure. not all are listed in a Haynes manual...unfortunately with intermittent failures it,s hard to diagnosis until it decides to fail. you can start checking thing,s like proper electrical connection,s, proper ground,s, semi clogged fuel filter, faulty collision sensor, have the fuel pressure tested, check for contaminants in your fuel tank, etc. there are many weird problem,s that can cause you headache,s...just take your time %26amp; don't overlook any thing that can possibly affect your fuel system...even a clogged filter will cause enough back pressure to change the sound that a pump make,s...best of luck!