Got fuel got spark turns over --nothing,crossfire injection,i have injecter pulse and 42-25 psi fuel pressure.if i spray gas in throttle body it runs till i stop spraying.

What testing have you done?
I looked at info for 94 blazer 5.7L engine.
Do you have spark, everywhere? Did you use a gage And check fuel pressure, with tbi fuel injection 9--13 psi. With throttle body injection you should be able to see fuel injector/s spray pattern, both fuel injectors. Even if injector/s spray pattern looks good, 5 psi won't start and run a v8.
Check for applicable trouble codes. My info shows your obd1, so you should be able to check some codes, yourself, if there are any.
You need air--fuel--spark--compression, proper amount at the proper time and it should start.

Must be your fuel pump has quit working. There should be fuel under pressure in the line to the throttle body, just by turning the key to on, not start. Not real high pressure like in multiport injected engines. Throttle body injection runs on about 20psi. If no pressure in your lines, find out why the pump is not working.

Normal cranking pressure is 70psi. It won't start if pressure is below 60psi.
Engines with multi port injection runs on 35-40 psi. and engines with throttle body injection run on 25 psi.

This sounds like fuel injection, is it? Or I think you would have said if it was a carburetor. But if fuel injection, it is the pump and the fuel filter's job to put fuel under pressure in the lines and up to the engine, or really to the injectors. If you have fuel pressure in the line, then you have fuel pressure to the injectors. (If not, check the fuel filter.) And then, it is the injector circuit's job to put the fuel into the cylinders.

Just first be sure the fuel pressure is correct. For throttle body injection, that resembles a carburetor somewhat-the injectors are in the throat, the required pressure is usually around 13-20 psi. But if you have multi-port injection, the pressure requirement is much higher, usually 40 psi or more, sometimes as much as 60 psi. If it is carbureted, though, it takes very low pressure, 5-7 psi, and you would need to check if the gas is actually getting inside the carb and filling the fuel bowl inside.

But back to the injector circuit: every injector has only two wires to it: a power wire and a ground wire. The power wire is constant voltage to the injector as long as the key is in run, or on, or in start. The injector is an electrical solenoid, and it gets the power on one side, and when the ground wire is grounded internally in the engine computer, the solenoid is energized, a fuel passage opens, and the injector sprays fuel out. This is called the injector pulse, it only happens for a split second. But you see why the injector must have fuel under correct pressure to shoot the right amount of gas into the engine. You can check the injector circuit, both power side and ground side, with just a simple test light. Post back if you want that, I can give you the procedure. Good luck, and probably good night.

I think I would be looking at the crank angle sensor and/or the cam sensors on this vehicle.It seems to me the engine isn't getting the signal to fire up.What happens when you squirt some fuel into the combustion chamber ? If it fires up I would be looking at cleaning the injectors.If it doesn't fire up What's the pressure on the fuel rail. does it have a buy pass pressure valve on the rail.Some suggestions good luck

year make and model ?

Im sure if its fuel causing your misfire but here are the fuel pressure specs depending on which one pertains to yours if your has a TBI Throttle Body Injected the the fuel pressure should be approx.9 to 13 psi if you have Multiport Fuel Injected (MFI) then the pressure should be approx. 41 to 47 psi if its Central Multiport Fuel Injected (CMFI) then the pressure should be approx.58 to 64 if you have Central Sequential Electronic Fuel Injected (CSEFI) then the pressure should be approx. 55 to 61 all these pressures are key on engine off if you start the engine and take a reading then you will have a decrease in reading by about 3 to 10 psi.

So you have used the Noid lights to see if the computer is pulsing the Injectors, and you have GOOD Kv on the spartk minimum 25-30 Kv's?

Also it might get gas but how much gas? you need to perform a volume test there is a certain amount of fuel the car needs her minute to sustain demand load variations.

Is it port injection or thortle body? What engine is ? if its port injection your fuel pressure is to low , if its a throtle boty i think 15-18 is minimum to keep the car running, might have a bypassing fuel pump in the tank.

Need more info.

if you've gotta dump more gas in it than it should be getting, it may have a large vacuum leak

this is happening because of your fuel pressure which is slowing down when you open the throttle to the intake manifold. you are losing fuel pressure somewhere from the gas tank and the fuel rail. do a fuel pressure check test. that might do the trick.