It will run till the fuel I pour in is used up then it dies. It has a new Maf sensor, coil, wires ic module,map sensor,crank sensor, cam sensor, rotor, cap,

What is the reason for disconecting the MAF

 

This definitely shows that you have a fuel related problem, but we knew that a few days ago when you posted pretty much the same thing.

If you have already checked/replaced the fuse and relay for the fuel pump (you can swap over the horn relay to the fuel pump relay), then the next step is to get the tank down. Once the tank is down, test for power at the fuel pump connector (you may need an assistant to turn the key on when you are down there with either a multimeter or a probe light). If you have power and a good ground, then the pump is the problem.

The reason for disconnecting the MAF sensor while you have the intake duct off of the throttle body is that it will not sense any airflow and will not allow the engine to run correctly if left connected.

 

Well I do not know why but the pump kicked in this morning and it started.I took the horn relay out put it in the pump relay socket put new relay I bought in the horn relay socket and it fired right up and the horn works.

 

Hopefully it keeps working for you. Did the old fuel pump relay test bad (did you try it in the horn relay position)?

 

No I did not test it. It could just be a coincidence switching relays. I have a relative who had a fuel pump that worked sometimes and sometimes it did not. He replaced it no more problems. It was not a blazer though.

Guess I will put up with the eratic fuel gauge for a awhile see what happens.

thanks for your help.

 

I have not drove the blazer since it decided to turn on fuel pump but it is dead again crank but no start so it was not relay, can hear, feel the relay clicking when key is turned on.

It is snowing up here again It will be a while before I get to working on it.

 

When you get out there next time, take a rubber mallet to the underside of the fuel tank, then try to start it. If it starts, the pump is the likely culprit and dropping the tank is warranted. Before you pull the pump, test for +12V at the connector to the sending unit. If you have power there, then pull the pump and disconnect the wiring inside the sending unit to the pump and test it. Sometimes the wiring inside the tank can break inside the insulation.

 

One more question. When the key is turned to on I can hear a faint noise coming from the BCM area. It sort of sounds like a pumping noise it lasts about 3 seconds and happens when the key is turned on and when the key is turned off. You almost have to have you ear down near the gas pedal to hear it.

The fuel pump made a louder distinct priming sort of noise when the key was turned on which it now is not doing, dead pump or something.

Is the noise from BCM area normal? Just wondering if BCM is faulty.

 

I have never heard a BCM noise like you are describing before...

 

Maybe it is something else. It sounds like something is being shut of when the key is turned off. It makes 3 sort of injnection noises, hard to describe.

I also took the shield of the gas tank and banged with fist on tank no diferrence.

I have a cheap code reader no codes but it probably cannot see any codes cause it is cheap but it shows the fuel system as not ready, used to show fuel system ready or someting like that.