Car won't start

Maybe pressure regulator

Yes, it should. If it is conventional (like other GM cars), the pump will turn on for a couple of seconds when key is turned to on. This will prime the system for starting. When key is turned to start (cranking), the pump is turned on again at the relay, and pump stays on as long as cranking the engine happens. Once engine is started, the oil pressure switch keeps the pump running.
The best way to check if pump is good is to use a fuel pressure gauge. If it does not have a test port called a Schrader valve on the fuel rail, the pressure gauge must be teed in somewhere convenient. But if you take off the line at the filter, some gas should come out with key on, and when cranking the engine gas should come out in a steady stream.

CHECK THE FUEL PRESSURE REGULATOR BY REMOVING VACUUM LINE AND LOOK FOR FUEL.

hi SXLYON.
this is all i could find,go tot this forum and see if it helps you out.
94 Chevy S10 Will Turn Over But Will Not Start
or this one.
https://www.cargurus.com/Cars/Discussion-t2646_ds611771
or this.
https://www.cargurus.com/Cars/Discussion-t21796_ds552801
or even this one.
1994 chevy s10 blazer turns over won start Google Search

The first thing I would check is fuel pressure. This type of fuel injection requires a minimum fuel pressure in order to operate. If fuel pressure is as little as one psi below minimum the vehicle will not start. You can try squirting a couple of shots of carb spray into the air snorkel while somebody cranks the engine over. If the engine starts and then dies you now you fpdeffinetely have a fuel issue. If the engine still won't start check for spark. Let me know what you find. Let me know if you have any questions and I'll do my best to answer them. Thank you for using FixYa.com!

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

Had friend put OBD diagnostics to it and error code indicated fuel pump ????? No code indicates replacing any part . Indicates testing ! pressure and flow testing , voltage drop testing the electrical circuit etc... There is a check valve in the fuel pump assembly that is suppose to keep pressure in the fuel lines an fuel rail . When the check valve goes bad allows fuel to drain back into the tank. Try turn the key on an off a few times to build up pressure . The PCM energizes the fuel pump relay for two seconds at key on .

Your problem may be one of the following:
First check or just replace the fuel filter. Usually located under the car in front of the rear axle, drivers side.
Next, the fuel pump may be worn out. Usually they get loud or stop working (running).
Next, check the fuel pressure regulator. Usually located on the front fuel rail, drivers side.
Is the vacuum line attached? Not leaking or rotted?
Also, do you smell a strong fuel odor when it won't start? May be one or more stuck-open injectors, or the coil pack is bad.
Checking these in the order listed will more than likely fix your problem.
The clicking noise indicates the battery can no longer run the starter, which also means the fuel pump won't run either.
It could be a fuel issue. How old is the fuel filter? Can you hear the pump run for a few seconds when you turn the key on? Try turning the key to ON without trying to start engine three times waiting for the pump to stop running each time. Then try to start the engine. If it starts, Its a form of Vapor lock caused by the extreme heat we have had lately, and a weak fuel pump.

If none of this works, try a new fuel filter first. From there have someone check the fuel pressure regulator and then the pump. If you are in need of a new pump, take my word for it and spend the money to get one from a Dealer, and not from your favorite parts store. Most parts store parts are made in China and they are JUNK.

STARTING / IDLING PROBLEMS / MISSING

Your problem may be one of the following:
First check or just replace the fuel filter. Usually located under the car in front of the rear axle, drivers side.
Next, the fuel pump may be worn out. Usually they just stop working (running).
Next, check the fuel pressure regulator. Usually located on the front fuel rail, drivers side.
Is the vacuum line attached? Not leaking or rotted?
Also, do you smell a strong fuel odor when it won't start? May be one or more stuck-open injectors, or the coil pack is bad.
Checking these in the order listed will more than likely fix your problem.
The clicking noise indicates the battery can no longer run the starter, which also means the fuel pump won't run either.

It could be a fuel issue. How old is the fuel filter? Can you hear the pump run for a few seconds when you turn the key on? Try turning the key to ON without trying to start engine three times waiting for the pump to stop running each time. Then try to start the engine. If it starts, Its a form of Vapor lock caused by the extreme heat we have had lately.

If none of this works, try a new fuel filter first. From there have someone check the fuel pressure regulator and then the pump. If you are in need of a new pump, take my word for it and spend the money to get one from FORD, and not from your favorite parts store. Most parts store parts are made in China and they are JUNK.
Have you hooked a scanner to the computer and checked the oxygen sensor(s)? If they are bad they could lean out the engine.

VAPOR LOCK
Check the following:
Cooling system working properly including fans.
Under hood fuel lines touching coolant or heater hoses.
Fuel lines under vehicle close to or not shielded from exhaust pipe, converter, muffler. Fuel lines pinched or crushed.
Fuel filter changed recently.
Fuel pump pressure.
Cheap(Bad) gas.

Fuel pressure regulator would cause low fuel pressure also. And hard starts. Can't believe dealer didn't check this also.

i would check the fuel filter if thats not it then it will most likely be the fuel pressure regulator make sure the vacuum line didnt fall off of it if that checks out then id say its your pump good luck i hope this helps