Hi all.
After replacing the fuelpump and trying to work out why my 2000 4.3 blazer wouldnt start I worked out i have no power between pin 87 on relay to the fuel pump.
I ran a wire from rely pin 87 to grey wire of fpump and blazer starts instantly and sat there humming blissfully..
I have since been trying to find break in power supply to fpump but havnt found any thing..
Can anybody suggest or offer insite how they remedied their power loss/ drop to fpump.
Thanks in advance and sorry about this novel.. my first post

 

I still havnt located fault/ break in power supply so i have put a wire with a 15amp fuse from the rely pin to fuel pump.I hope to find the problem and make a proper repair once i can work out whats actually wrong.
Any suggestions would be greatly received. Thanks

 

Have you replaced the fuse?
Even if it is looking o.k. - has happened to me before. Changing the pump had the wires touch shortly, fuse blown but not really visible as it was at the very end of the thin section. Sticking the head underneath the dash with all the shadows didn't see it being blown.

Checked as you did, with a direct wire, then ran continuity checks along the wiring which was found good until the fuse block. It's when we discovered the bad fuse.

 

thanks for comment error_401. I have changed the fpump relay with one of others in the box but not a fuse.. i thought fpump runs through ecm2 fuse which seems to be okay. Is this the fuse you changed?

 

1 week on the road and no problems this far.. thankfully..
I am thinking of researching and fitting an external F/pump relay and keep my home made loom.. another thought was to pull the under hood fuse/ relay box apart but have seen a couple of threads on here about this and wondered if this is worth the effort amd chance of upsetting something else