My blazer has been very reliable this past winter with minimal problems, however, just this morning it would not start up.

After replacing the distributor cap and rotor (As I had nothing else to go on - it needed replacing anyway) and shocking the crap out of my arm proving it had spark from the coil, I noticed the fuel pump did not make it's familiar buzzing noise when the key is turned on.

I want to check my way back to the fuel pump before I conclude the pump is toast and change it out. So far I have checked all the fuses, and I want to verify the wire going to the fuel pump. Where would that be located?

Thanks!

 

You will also want to check the fuel pump relay as it is a common issue on these trucks. Switching it with another relay of the same type is easiest for a quick test. Both the horn relay and the fog lamp relay should be the same as the fuel pump relay.

As for checking the wires to the pump, it is easiest to check from the pump forward rather then the other way around.
Pull the plug from the pump and have someone turn the key while you check the voltage there. If you get 12v at the plug then it is likely that the pump is gone.

If you don't get 12v there then you will need to start checking the wires up front possibly even including potential problems in the ignition switch itself.

 

the fuel pump relay is fine, so I'm thinking the fuel pump is toast.

I was looking on the internet and it sounds like the the fuel pump is really unreliable, so I don't know if it is worth replacing it. I wonder if it is worth it to get an inline electronic fuel pump and mount that instead. Has anyone gone that route?

 

Fuel pump is a common subject around here. I've never heard of an inline replacement and it won't work. The fuel pump doesn't draw directly from the tank. One part fills a "cup" & the second part draws from it to send pressurized fuel to the line. If you wire to an inline pump you'll be trying to draw from an empty cup.

 

the fuel pump failing is a common problem with the blazer and depending on the year of the blazer it can be expensive to replace but not that difficult to replace with 2 people, you can attempt to relieve the fuel pressure in the rail on the right back hand of the engine from the schreader valve and the try to put the key to run position and check for noise. if that fails you can do the tried and true taking a whack on the bottom of the tank with a rubber mallet prior to puting the key to run position if all else fails time to look for a fuel pump.

 

Go to the fuel pump prime connector and wire it directly to the battery. This by-passes all the relays and provides battery voltage to the pump directly. The connector is located on the firewall.

 

IT STARTED about 4 yrs ago but to day it will not start back up . i have done some red neck thing by primming it to start when i go to start it but the primmig did not work to day is it the fuel pump

 

Use fuel pressure gauge indication if there is your fuel pump problem. If the pump pressure is below 3 bar, it will need to be replaced.

 

I've replaced 10 fuel pumps-2 within 2weeks -check after manufactued pumps-delco no good-check ratings on manufactor-last pump over 2 years ok-replaced due to broken return tube on pump!-plactic crap-next pump over 1 + years-ok -sorry can't find make-autozone product-around $150 and lifetime warrentee!- I have 248000 on my blazer-just passed smog ca. I've fixed and modified and going to keep-thanks for this site-will be visiting more in future!

 

Went out to start my Blazer this morning and it wouldnt start. It stumbles but won't run. Pulled the lines off of the filter and turned the key on the pump ran for 3 to 4 seconds then shut off. Is the fuel pump supposed to shut off or stay on all the time the key is on?