1997 Chevy Blazer Won't start

[ezh10111]

I have a 1997 chevy blazer one day while driving it turned off on me and it did not want to turn on again until i changed the spark plugs. The truck ran for a couple of hours after i changed the spark plugs then it died again.I have now replaced the fuel pump and the ignition switch, the gas is flowing to the engine and im am getting spark at the wires, but the truck wont turn on.If any one can HELP me please do so because i need it.

[Airjer_]

What happens if you give it a shot of carb spray into the intake? If it starts than you still have a fuel issue.

[ezh10111]

Ok i sprayed carb cleaner and it started, but its having problems starting and also my gas tank is making a whisle noise.

[Airjer_]

Check fuel pressure!

What brand pump did you install?

[ezh10111]

I dont know i got it from a car truck in a junkyard and also it only tells me how much gas i have when its off, but when its on it does not.

[ezh10111]

could it be that i got a bad fuel pump.

[ezh10111]

were can i find what the fuel pressure supose to be.

[Airjer_]

You'd want to be in the neighborhood 0f 58-64. These have a popet type inject and they require a minimun fuel pressure to work. Less than 55-57 psi and it will not start.

[ezh10111]

I have been starting the truck with carb cleaner and black smoke is coming out the back pipe, but then it dies.

[ezh10111]

Could it be the fuel injectors

[Airjer_]

It could be a lot of things. The fact that it starts with carb spray tells me a lot of things are working. The first step would be to check fuel pressure. If pressure is low there is no sense worrying about anything else.

[ezh10111]

I reaplaced the gas regulator but still nothing.

[MT-2500]

As they are trying to tell you check and confirm good fuel pressure.

Here is the procedure.
The only true test on a fuel pump is to check the direct fuel pressure from fuel pump.
A quick test is to block off the return line and see if fuel pressure comes up to 75-85 lbs.
But do not run the pump at full pressure very long.
Also when testing fuel pump and pressure you need to tape a gauge to outside windshield or outside mirror and drive it on the road for 20 -30 minutes
until the pump gets has run a while to check for a pump fading out after hot.

Hard to start cold or hot and fuel pressure testing guide lines.
Check cold start fuel pressure.
Check engine running fuel pressure.
Check engine running on the road fuel pressure.
Then shut it off and watch for fast leak down.
Pinch off at rubber part or block off return line and check full pressure.
If pump has full pressure with return line blocked and low pressure without it blocked most usually the fuel pressure regulator is leaking or not holding pressure.
Later V6 and V8 gm engines should have 60-66 fuel pressure.
Cold start should be 64-65 lbs of pressure.
If you do not have full fuel pressure on a cold start the injectors will not squirt fuel.
Do not leave home without it.
Engine running should be 60-66 lbs pressure depending on engine load.
Full pressure with return pinched off should be 75-85 or more.
And if it has a fast leak down after shut off you have a leak in system.
Post back fuel pressure readings.

[ezh10111]

i can't even start the truck and i am running a little low on money to get fuel pressure tester.

[MT-2500]

Some places rent or loan fuel pressure testers.
Got better and cheaoer than throwing parts at it.
Do you proper testing first.