oka guys i think i have found the problem. I finaly got my hands on the wiring diagram and figured out which pin is the signal for the fuel pump to turn on. The book tells me that this pin should have a reading close to 12v when the key is turned on, However when i tested this the pin did not have that. It barely registered one volt. Now the question is, is it more than like the connector or is it something else. I tested the relay block and got a 12v reading there. Now my next question is that there is three relays in the glove box. The center one is considered to be the fuel pump. What are the other two for.

 

ok dont know what the relays are for but I talked to my brother today and he said it is next to the gas tank on the frame, but yours is different because your tank is in back and his is on the side(s10 vs blazer).

 

I had a nice long reply full of valuable info, however I guess it took too long to type and this site logged me out. I lost all of it. I will try to recreate it for you.

I used to know what all the relays are for, but have forgotten.

Replace the relay to eliminate it as a possibility, then are cheap (less then $10) and easy to replace.

The is another circuit that will kill power to teh fuel pump. It is the oil pressure sending unit. It is a safety device, no oil, no fuel, no fuel, no way to destroy the engine. It could also be a fualty ignition switch. Mine would trip my security system and wouldn't let me start the truck, however after 10-15 minutes it would start just fine. Dealer replaced the switch no charge, warrenty.

If your still reading and niether of those are the problem, fuel pump is shot. Which is what I suspect is the problem in your case.

Your gas tank has is located under the drivers side passengers seat. It has 6 hoses and 2 wiring harnesses. One of those wires is the ground, I doubt that is your problem, but you can check when you drop the tank. There is one bolt and one nut holding the two straps in place that hold your tank in place. The other side of the straps are hooked into the frame, push up and pull them out from the frame to release them. You will have to tilt the tank in order to remove the hoses and connectors. The harnesses and hoses attached to the fuel pump assembly are the easiest to remove. The hoses are quick clips, push the right parts and they come off. Easier said then done. Soak the other 3 hoses with WD-40. It softens the rubber and makes removal and installation much easier. Otherwaise you could spend an hour trying to get them off and might break something. One rubber hose is located on the front of the tank (towards front of truck), and the other two connect to the back of the tank and attach to your gas cap.

More useful tips.
Debris will fall off the top of the gas tank when you tilt it. Most likley in your face, wear eye protection and keep your mouth shut. [:'(][:@]
Gas weighs roughly 8 pounds per gallon. 10 gallons = 80 pounds. The tank weighs roughly 20 pounds. IF you can bench that much, much faster and easier then using a jack. Otherwise use a jack. I would bench the tank in and out, then use my knees to hold it in place while I worked with my hands to install the straps, nut and bolt.
Clean all the debris off the top of the tank BEFORE you take the old pump assembly out. Don't let any of that crap get in the tank. I drained my tank and used the gas in my mower. Get new gas after you put it back together.
Get a new rubber gasket when you get the pump assembly, should be part of the kit.
Spend the $5 and get a new strianer too. If you don't plan on dropping the tank agian.
The new assemblies come with a new gas gauge sending unit. Your gas gauge might not work like the original. Some drop qucik at first, and slow down at the end. Some drop real slow at first and real quick at the end. This is normal.
You MUST have the code off the old unit to get the correct replacement. The only way to get that code is by dropping the tank.
If the vendor doesn't ask for the code, find another vendor, they WILL sell you the wrong part, and more then liekly the one you need will be out of stock.
Realize the new fuel pump assemblies cost $250 and up. GM quaoted me a price of $340. You get what you pay for. I went with a lifetime warrenty pump from AutoZone for $285.

It took me about 3 hrs to swap out my fuel pump assembly in the '00, and a month in the '87. Had other issues to deal with on that one, like rust holes. This includes 45 minutes running to the part store with my old part in my hand.

If you have more questions post up.

 

Revving this thread, since I may have to do this, and I think Hanr3's tips were really helpful...