Fuel pump relay?


fp1529
04-23-2012, 07:49 AM
I have a 99 Suburban 1500 5.7 with 160,000 miles, original fuel pump. Yesterday the truck would not start and I realized I did not hear the fuel pump. I tried to crank it today and it fired up, I could hear the fuel pump. When the fuel pump goes is it sporadic? Could it be the pump relay?

MT-2500
04-23-2012, 09:12 AM
I have a 99 Suburban 1500 5.7 with 160,000 miles, original fuel pump. Yesterday the truck would not start and I realized I did not hear the fuel pump. I tried to crank it today and it fired up, I could hear the fuel pump. When the fuel pump goes is it sporadic? Could it be the pump relay?

Fuel pumps fail in several different ways.

When key fist turned to on you VCM sends a 2 second ground prime up signal to fuel pump relay to turn on fuel pump.

To test relay check for the key on prime up signal or engine cranking fuel pump relay ground signal.

Or some just switch out relay with a known good relay.

stever111111
01-27-2016, 08:06 PM
I have a 2001 suburban. I was removing snow one night, was pulling from a garage, ran over the snow pile and it died.. Now it starts first thing in the morning (can hear fuel pump kick in) but stops after a minute or two. like turning key off (no sputtering) then it cranks with no start and no fuel pump kick in. Question: Seems to me the pump is over heating and cutting out. Is there a ground wire under chassis I could have broke loose while plowing? Can a relay get hot and short out? What can it be guys and gals?

j cAT
01-28-2016, 10:09 AM
I have a 2001 suburban. I was removing snow one night, was pulling from a garage, ran over the snow pile and it died.. Now it starts first thing in the morning (can hear fuel pump kick in) but stops after a minute or two. like turning key off (no sputtering) then it cranks with no start and no fuel pump kick in. Question: Seems to me the pump is over heating and cutting out. Is there a ground wire under chassis I could have broke loose while plowing? Can a relay get hot and short out? What can it be guys and gals?

being new member the best way to solve your problem is to post this as your problem by creating a new posting . your post not someones old issue. pumps do overheat from low fuel . also you have a filter. then there are wires next to the fuel tank to the frame rail. relays are not a common failure but the pump is when you run down the fuel below 1/4 tank. wires on top of the tank can be damaged like if someone replaced the 2001 pump with the new pump this requires wires to be cut and a new connector to make the connection to the new pump. well these need be soldered and sealed with heat shrink many mechanics do not do this so then it fails .

stever111111
01-28-2016, 10:14 AM
Thanks Cat, I'll look for the wires. The tank never gets below 1/4. Now I must learn how to start a thread

rhandwor
01-30-2016, 10:11 AM
I have a 2001 suburban. I was removing snow one night, was pulling from a garage, ran over the snow pile and it died.. Now it starts first thing in the morning (can hear fuel pump kick in) but stops after a minute or two. like turning key off (no sputtering) then it cranks with no start and no fuel pump kick in. Question: Seems to me the pump is over heating and cutting out. Is there a ground wire under chassis I could have broke loose while plowing? Can a relay get hot and short out? What can it be guys and gals?
Their is a ground wire under the vehicle look on the frame near the fuel tank.

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