After replacing the spider, plugs, dist cap and rotor, oil, and gas filter my 96 Blazer has been running like a top for several weeks now. The wife tries to start it this morning and no go. Not getting fuel so I verified at the shraeder valve and no pressure. Listened for the pump and no sound. Just to make sure the filter was not blocked up I took the inlet loose and no gas. Probably the fuel pump but I am hoping for better and thought why not check the pump relay. I tried applying 12V to the test lead and nothing there. The Chilton drawing shows the pump relay 12 V input as being switched away from the Red test wire and connected to the pump. This I think would be the energized position. When I test the red test wire resistance to ground it shows open. If anyone has any thoughts on this it would be great. Can anybody tell me where the pump relay is located? I can't seem to find this information in the Chilton book. I guess the next step will be to get the connector loose at the tank and look for 12 V. Thanks for any ideas or suggestions!

 

I have identified the fuel pump relay as the glove box left of three relays. The center contact is the relay switch normal closed and I did a continuity check between the Red TEST terminal that is on the driver side engine compartment wire harness close to the firewall. I tested the relay (all three) for proper operation and switch continuity. I still read an open circuit between the Red wire and ground. The chance of it being anything other than the pump motor being open is looking pretty slim. I was wondering if the pump is fused internally or if this is the way they normally fail. Next I will try to get the connector off at the tank just to make sure. Unfortunately this has happened with the Blazer parked on the street and we have a very short and inclined driveway. Driveway is flat only at the top and dropping the tank on the street would not be the thing to try to do. Can't blame the Blazer for that! This forum has been the only reliable info I have found and I appreciate the help!

 

Having a similar problem, went to try to start my blazer after work and no luck. It turns over, but I have no fuel prime. The fuse panel under the hood has several of the same switches so I swaped it with the fog lamp just to see if it was the switch and the same result, nothing.
For a while the gauage has been on the frits so it is a good indication that it is the sending unit finally failed.
When I get back to it, I'm going to check if the security light comes on to see wether it is an ignition problem or not. Could be something as stupid as a cap and rotor.
Allways use AC Delco and not after market, it will lead to further problems in the future.

 

I should have finished this thread a couple of weeks ago, sorry. My wife's Blazer is back on the road and running better than ever. My personal experience with changing the fuel pump can be best described as a job for you and your buddy. Having never done it before all I can say is that extra eyes and mental support ( as you lay on your back in the driveway) cannot be understated in importance! Knowing what I know now, if it came up again I would do it no problem. Reading some other posts here on the forum has been without a doubt the only real source of knowledge. Most of us that have come here I would guess are not professional mechanics but do take interest in seeing how things work. It can definatly be a leap for many of us to start disassembling an expensive and in many cases, such as mine, the only mode of transportation. A little common sense can go a long way but it is those bits of verifiable information that keeps you from putting yourself through unnecessary work and pain. Those questions have obvious answers only after you know what the answer is. They can be real deal breakers, marriage breakers and in general a major hassle. The price that the dealership and local garages wanted to change the pump to me seemed unrealistic. If I had more money than free time I would had paid them and gone on. But, that was not the case and if you are in the same position, believe me it is a doable job if you have a few things to work with. Number one, the blazer forum!
All I would like to add to what you will find elsewhere in the threads is some specific GOTCHAS.

I refer to a 96 Blazer 4.3LVortec w/4doors
#1 When your fuel pump will not run There is a RED test wire on the driver side engine compartment side just infront of the Brake master cylinder an vacume reservoir. It is there and it is a loose red wire with a sta-con type connector coming from the wire harness. This is the pump test wire but it is not directly connected to the pump. It goes to the pump relay that is located in the glove box, one of three identical relays located under a cover. Remove the plastic snap in cover and this relay is the left one as you face it. My pump worked perfect through a series of age related failures with the fuel injection system. It continued to work perfect for 1 weeks after injector major surgery and right up to my wife getting home from a 200mile hiway trip, parked it in the driveway and the next day nothing! Talk about a deal breaker! How could this happen? Well it can it did and we are again happily married.
So the test wire goes to what are a normal closed contacts and the relay common goes straight to the plug that is connected to the pump. I now know that if you measure "open circuit" to ground at the red wire there are two places to first check before dropping the tank. You can exchange the pump relay with the other two identical relays freely and if it is a relay problem your pump will start working and something else on the vehicle may not work. If there is no change you can unplug the connector from the pump at the tank.
#2 After searching for a clear image of what and where this connection would be as I laid on my back I became a bit frustrated. Maybe if I had hosed the tank area off with water, and I do suggest this to do first for two reasons. After you raise the rear of the blazer and have it on stands(absolutely mandatory) you can look at the to of the tank just above the rear axle drive housing and clearly see the three fuel connections to the pump. The pump fills a hole about 4 inches in diameter and these fuel lines are on the rear side and facing forward is the electrical connector. Reach up forward of the fuel lines the connector is a waterproof push in with a side latch and it can be release. The number two reason for hosing it down is that unless you are wearing goggles you will time after time get dirt falling in your eyes. This can be more of a problem than the job!
With the electrical plug loose you can verify a good continuity to the pump connector. I gave up because I just could not get a good grasp on where this electrical plug was and with my eyes full of dirt I gave in to dropping the tank.
#3 You must remove as much gas as possible from the tank. You can't siphon the gas out! I know now that there is a plastic ball that blocks the entrance to the gas tank from the filler hose. This was a real question, why can't I put a hose into the tank from the filler cap. You can't do it!
#4 To gain access to the gas in the tank, (especially if it is 3/4 full) after loosening the band clamps at the rubber hose filler tube, you can loosen the two strap bolt nut hangers enough to let the rear of the tank free to drop enough to get the large or small rubber hoses loose. These are formed rigid hoses with little "give". You can then put a hose in and siphon the gas out. I would not suggest attempting to drop the tank with more than a gallon of gas in it!
#5 I can't stress how important it is to carefully remove the three gas lines at the pump and do so without breaking them. This can be done! I do not not know the tech names of these and I have read here that a inexpensive tool can be bought at local parts house to remove these. Get one if you can.
#6 There is a vapor line at the front of the tank that if you do not remove the hose before you release the two steel straps you will break it off!

Getting these 4 fuel lines disconnected without breaking them will be the difference between an easy reassembly and a successful job and one that will have expensive extras and check engine trouble codes. I will add more posts to my experience later. The wife is calling and I must obey. Lastly the descriptions I have given is not a step by step on doing this job by any means. It is only to make these points that I had more difficulty in finding answers to. For the details and "proper" safe methods I have to say that I would like to drop one "go to" members name, swrtlkk. Thank you for the time you obviously have invested in helping the rest of us! He has my vote for master Blazer mechanic and the hot pizza and beer prize! Thanks!

 

thanks for the feedback I'm gonna try the relay trick.