95 blazer not getting fuel new tank,sending unit/pump, relay. has 4.3l cpi vortec engine

You have to reove the upper plenum. that is the part on top of the intake that looks like a dome on top of the lower intake.There is 8 10mm bolts around the outside of the dome part. the disconnect the fuel lines at back of lower intake and remove the cpi unit.

check for spark at the plugs check firing order in correct direction on cap in relation to direction of dist rotation remove cap wind engine to see that distributor drive gear hasnt stripped a tooth if these are ok if its electronic dist the module could be faulty

Issue with PCs Valve Check for vacum lost cracking rubber connection Pre-Heater and Primer System Mal-Functional Check also for Idle sensor Relay for bad connection....good luck

Removal & Installation
To Remove:

1. Properly relieve the fuel system pressure.
   
2. Drain the fuel tank through the filler pipe.
   
3. Support the fuel tank.
   
4. Remove or disconnect the following:
   
   
   
   • Negative battery cable
     
   • Filler neck
     
   • Shield and tank straps
     
   • Fuel lines and vapor hose from pump and tank
     
   • Electrical connection from fuel pump
     
   • Fuel tank
     
   • Fuel pump/sending unit assembly by turning the locking ring (located on top
     of the fuel tank) counterclockwise using a spanner wrench
     
   • Fuel pump from the fuel lever sending device

To Install:

1. Install or connect the following:
   
   
   
   • Fuel pump in tank with new seal around opening
     
   • Tank and connect fuel lines and vapor hose
     
   • Tank to the frame
     
     
     
     1. Torque to: 33 ft. lbs. (45 Nm)
     
     
   • Shield
     
   • Fuel filler neck and clamp
     
   • Negative battery cable
   
   
2. Refill the tank.
   
3. Run the engine and check for leaks.

View of the in-tank fuel pump assembly.

A spider injector is located underneath the intake plenum and this is multi-port. Otherwise you have a throttle body injector system. Vortec engines have spider injectors and they are super expensive to replace ($400.00- 850.00) each ! There is only one spider injector for each engine it has 6 legs/fuel tubes that go to each cylinder.

1. Does the pump actually run (key on engine off) pump should run for 2 seconds and go off and can be heard if you listen at the filler neck with the gas cap removed)
pump not running - Check relay (replace if bad) check wiring/fusese

Pump runs... go on to #2...

2. check the gas guage. is the gauge reading in the normal area it would read in or is it way way off like WAY above full or way below empty? This is a sign the electrical connection at the pump is plugged in backwards and the pump is spinning the wrong way and not picking up the fuel... (This is easy to get plugged in backwards inside the tank when installing the new pump)

3. Check for feed, return and vent lines being installed wrong where they attach to the tank... they can easily be hooked up wrong and fuel is either pumped up in to the return line or pumped in to the fuel tank vent line..

4. check for kinked or crushed fuel lines from tank to engine.

5. check fuel pressure regulator to be sure its not stuck open.

I'd put more fuel in it and see what happens. But I'm going to guess that you are having a problem with your injector. These cpi systems are notorisous(<spelling?) for problems.

you have to put a guage on it to find out the pressure it may kick on but not enough pressure

Hello;
First you need to have your fuel system tested. It sounds as though the relay and pump have gone out. When you turn the ignition to on the pump should energize for 2 seconds and stop. The pump will deliver fuel after startup. Poor performing pump equals poor performing vehicle. With the vehicle not staying running when it did start, I would check the fuel pressure and then replace the pump. You can check the fuel pressure regulator by pulling off the vacuum line and see if you have fuel in the line. If you do the regulator is shot. The fuel pump relay also needs to be checked for operation especially if the fuel pump is not working. Also check your rollover valve to be sure it has not tripped.
Thanks;
Rich
RPM Norhtwest

in the fuel tank , MIninum fuel pressure for the vehicle if it has a vortec engine is 60 PSI the vehicle will not run on less than 60PSI
If you have a non vortec engine the fuel pressure is around 9 PSI
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