96 blazer hard to start when cold and missing

have a 1996 blazer w in the serial.

just started this. but when the truck has sit in the cold for a day or so it is a bit*h to get started after it finally starts it runs rough and misses. after it warms up to running temp everything is fine like it never happend. also had a friend check the fuel pressure with gauge it was around 62 while running and about 62 when key was just on. didnt drop any pressure after it was off either. i also replaced the ignition control mod. and that wasnt it.
any ideas with this?
tune up was about 15 to 20,000 ago new wires cap filters and rotor button and plugs.

actually the tune up was about 10,000 ago.. sorry

I have heard that when the truck is warming the computer takes over for the sensors until normal operating range is met. Once normal temperature is met, the actual sensors (O2 sensor and such) take over. I guess your problem would happen if you had any mods to the vehicle or if your ECM (computer) had something wrong with the sensor presets. Maybe you can reset your computer. You can also check your EGR valve and PCV valve. I am not an expert as you can tell, I am still learning myself. I thought that maybe something here would help you out or lead you to the right direction. Reply back if you find out anything.

I would suggest you change your fuel filter if you haven't ever.

Would definite cause that.

Did you gap the plugs properly?