My 2001 Chevy Blazer won't start when its cold.

Bad fuel pump, fuel filter, it may not have enough pressure or you aren't getting spark

sound you have a blown clutch slave cylinder

see if the fuel pressure drops after sitting it shouldn't

If it isn't the gauge in the dash then it will be the fuel level sesnor in the gas tank. This will require dropping the tank to getvat it. Not a cheap'repair, part is cheap, labor won't be so shop around. I know some guys have just got a tank from salvage then they could just swap out the whole thing quickly.

you have an electrical problem . check fuel circuit fuses, relays and sensors

The question is why?

Do you live where you don't ever use 4 wheel?

Why would you now a vehicle is 11 years old,
even worry about, what will be a hobby or some
sort of restoration project

You won't get any improvement in gas mileage
& you absolutely have to do all that work yourself

It simply isn't done professionally & you couldn't
afford it if it was.

Buy a different vehicle or trade with someone who wants
4 wheel & has what you want.

Try giving it a shot of starting fluid. You don't say if it's actually firing. If it tries or runs for a few seconds off of the starting fluid then try changing the fuel pump relay. It's inside of the glove box on the left hand side behind the little door. If that doesn't work it's most likely the fuel pump.

freon level is low. add r134 refrigerant and your problem will be solved.

swng,
1) Is the service engine soon light ever on when engine is running?
2) Per your description I would look at the ECT sending unit. It sends coolant temperature information the the Engine Control Module for proper fuel delivery for cold engine start. It may have lost its calibration.
Let me know.
Regards,

if it turns over there are a cocuple of things to check. crankshaft sensor and the coil pack maybe the computer.id start with the crankshaft sensor