1991 Chevy S-10 Blazer FUEL PUMP Problem

Hi guys! My 91 S-10 4x4 V-6 will not start! The last couple of weeks before I parked it, it would idle down and then I would have to stop and let it rest and it would eventually return to a normal idle. I parked it for two weeks and when I went back to start it, it would just turn over - it sounds like it is not getting any fuel. So I replaced the fuel pump today and it still will not start. I turn the key and I am unable to hear the fuel pump come on. I unhooked the tank fuel hoses from where they connect to the fuel lines to see if any fuel would come out...none - they are dry. I checked the 10amp fuse that is tied in to the fuel pump control, and it is good. Any ideas??? Thanks in advance!

plugged fuel filter?

Before I replaced the fuel pump, I checked the lines going in and out of the fuel filter and there was fuel on either side. I assumed from this that fuel had been running through the filter ok.

When I turn the key I don't hear anything from the fuel pump. I am wondering if there is a short somewhere? Is there anyway that I can hook the fuel pump up directly to the battery to see if it is the fuel pump or the wiring going to the fuel pump?

Thanks!

replace the fuel filter and seeing fuel on either side of the filter doesn't mean it is ok.

Also, check your fuses to see if the pump fuse was popped if you have one.

There is a 12v pump prime wire located near the drivers side of the firewall. It is a red wire with a plastic end of it not connected to anything.

Can i simply splice into that wire and run it straight back to my fuel pump? If so, which wire on the fuel pump should I connect that prime wire to? Thanks for your help!

I did check the fuse & it is good.

I did check the fuse & it is good.

Check and see if you have power at the fuse. Also like LT said could be the filter.

Would the pump still be coming on even if the filter was bad? How can I check and see if I have power at the fuse? Thanks for the help!

Would the pump still be coming on even if the filter was bad? How can I check and see if I have power at the fuse? Thanks for the help!


Use a volt meter or test light at the fuse, pull the fuse and check for power, should have power on one side of the prongs where the fuse plugs in when key is turned. Yes, the pump should still run even with a cloged filter. Maybe the new pump is quiet and your just not hearing it. I don't hear my pump run either but Blazer runs just fine.

I am getting electricity at the fuse box. When I unplug the hose coming from the fuel pump, and turn the key on - no fuel comes out. All of the hoses coming from the fuel pump are dry. Any ideas? Thanks again in advance!

I am getting electricity at the fuse box. When I unplug the hose coming from the fuel pump, and turn the key on - no fuel comes out. All of the hoses coming from the fuel pump are dry. Any ideas? Thanks again in advance!


The next step would be to verify your getting power to the pump and that it is running. You say you changed the pump, is there any chance at all that you hooked the wiring up wrong or forgot to plug in a wire? Not saying thats what happened, but it does happen, even to the best of us.

I double-checked how I hooked the pump up.

The new pump came with an adapter that I had to attach to the pump w/the nuts provided. The adapter coming from the existing pump assembly then plugged right into the new pump's receptable. How can I make sure that the wiring at the pump i good?

I double-checked how I hooked the pump up.

The new pump came with an adapter that I had to attach to the pump w/the nuts provided. The adapter coming from the existing pump assembly then plugged right into the new pump's receptable. How can I make sure that the wiring at the pump i good?


Just check the hot wire at the pump with a volt meter or test light and make sure you have power. Might even pull the pump and test it on the work bench and make sure it will run. I guess its a posibility you got a new pump that was bad.

It is Fixed!! You all will never believe what it was. Whether through intentional sabotage or just a one-in-a-million happenstance occurrence, the plug that goes into my fuse box that obviously runs to various parts of my vehicle was unplugged. I plugged it in, and viola! the truck started right up! Thanks for all of your help; it was only through the troubleshooting process that I was able to figure this one out. First, I did not know there was such a plug, and second had I known it was there I never would have thought to check it. Thanks again.

It is Fixed!! You all will never believe what it was. Whether through intentional sabotage or just a one-in-a-million happenstance occurrence, the plug that goes into my fuse box that obviously runs to various parts of my vehicle was unplugged. I plugged it in, and viola! the truck started right up! Thanks for all of your help; it was only through the troubleshooting process that I was able to figure this one out. First, I did not know there was such a plug, and second had I known it was there I never would have thought to check it. Thanks again.

Glad to see you on the road.

Now charge your battery up.

Have your checked the fuel pump relay? have you traced the wiring to the pump? Did you replace the whole pump assy or just the pump? if just the pump check connections

How low have you've been running your gas tank, since it is an 1991 there might be some sediment build up on the bottom of your tank, the problem being is that the pump is probably located in the gas tank. *First test the filter. unplug the fuel line contecting from the pump to the filter, on the filter end and have someone turn on the key over, some gas should come spitting out, if not then its a pump problem. If gas does come out plug the line back in. Then disconnect the line running between the filter and the engine on the filter side, gas should come out as well, if not then you have a clogged filter. If there is gas coming out in both scenario's and your engine wont start, then its most likely not even fuel problem, check something else. If you isolate the problem down to the pump, then that is what needs to be replace, I recommend a mechanic to do this task, most likely this model is gonna have the pump inside the tank. leave it to the pros, thats why they get paid so much, let them syphon the gas out, diconnect the tank, then the pump. as for me I dont ever wanna do that. good luck.

*this is just a recommendation and should not be used a professional advice, always consult your car's owner's manual or a chilton's or Haynes

How low have you've been running your gas tank, since it is an 1991 there might be some sediment build up on the bottom of your tank, the problem being is that the pump is probably located in the gas tank. *First test the filter. unplug the fuel line contecting from the pump to the filter, on the filter end and have someone turn on the key over, some gas should come spitting out, if not then its a pump problem. If gas does come out plug the line back in. Then disconnect the line running between the filter and the engine on the filter side, gas should come out as well, if not then you have a clogged filter. If there is gas coming out in both scenario's and your engine wont start, then its most likely not even fuel problem, check something else. If you isolate the problem down to the pump, then that is what needs to be replace, I recommend a mechanic to do this task, most likely this model is gonna have the pump inside the tank. leave it to the pros, thats why they get paid so much, let them syphon the gas out, diconnect the tank, then the pump. as for me I dont ever wanna do that. good luck.

*this is just a recommendation and should not be used a professional advice, always consult your car's owner's manual or a chilton's or Haynes

This thread has been dead almost 3 years, please check the dates before posting. Thanks.