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1996 Chevy Silverado Wont Start

JAYHAWKER135

By JAYHAWKER135
in Ask A GM Technician

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JAYHAWKER135 New Member

JAYHAWKER135

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My 1996 chevy silverado C1500 5.7 wont start. I have replaced fuel pump, fuel pump relay under hood, checked fuses, replaced module in distributor cap. When you turn key to on position i dont hear the fuel pump come on like usual and the lines have no pressure and are not getting fuel. motor will crank, and plugs get spark but wont turn over or get fuel. Im running out of ideas and really need help. Please if anyone can help, im getting tired of dumping money and not getting any closer.

beave84 Enthusiast

beave84

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My 1996 chevy silverado C1500 5.7 wont start. I have replaced fuel pump, fuel pump relay under hood, checked fuses, replaced module in distributor cap. When you turn key to on position i dont hear the fuel pump come on like usual and the lines have no pressure and are not getting fuel. motor will crank, and plugs get spark but wont turn over or get fuel. Im running out of ideas and really need help. Please if anyone can help, im getting tired of dumping money and not getting any closer.

 

 

Have you checked the maxi-fuse in the underhood fuse/relay panel under the hood. i ran into this, use a light style tester and make sure both sides of the fuse have power when the key is on, both sides should glow the same. I had one that was bright on one side and dim on the other, was broke inside but still made just enough contact to light the light but any load and it opened up.

JAYHAWKER135 New Member

JAYHAWKER135

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if that is a block style reylay ya i have checked it and replaced it. there is a conector in the back of the truck that plugs into the top of the fuel tank to power the pump, i get constant power on one leg but not any other legs(the conector has three legs) i dont know if that helps you narrow it down for me or not. thanks

beave84 Enthusiast

beave84

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if that is a block style reylay ya i have checked it and replaced it. there is a conector in the back of the truck that plugs into the top of the fuel tank to power the pump, i get constant power on one leg but not any other legs(the conector has three legs) i dont know if that helps you narrow it down for me or not. thanks

 

 

Yeah the pump uses a hot and ground and the other is for the sending unit. If there is power but no pump running Id say the pump is bad. This no joke...turn the key on and give the tank a good thump under the fuel pump and see if it kicks on.I didnt belive it either but a tech told me to try it one day i was stranded and it came on and ran till i got home but it showed the pump was junk.

JAYHAWKER135 New Member

JAYHAWKER135

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the pump is brand new though, i even hooked it up to 12v to test it before i even put it in. it worked. and when i put the truck back together and it still didnt start, i even hooked the old pump up to 12v and even it worked, but it wont work on the truck for some reason. thats what i mean, i am getting really frustrated, i know its right under my nose but im not able to figure this out, im just about to take it to the shop but i would really rather fix it at home instead of trailering it around

beave84 Enthusiast

beave84

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the pump is brand new though, i even hooked it up to 12v to test it before i even put it in. it worked. and when i put the truck back together and it still didnt start, i even hooked the old pump up to 12v and even it worked, but it wont work on the truck for some reason. thats what i mean, i am getting really frustrated, i know its right under my nose but im not able to figure this out, im just about to take it to the shop but i would really rather fix it at home instead of trailering it around

 

 

Have you unplugged the connector from the tank and tried plgging the old pump into it to see if it'll run since you know it runs. when you tested it did you just use a wire to the battery + and -?

beave84 Enthusiast

beave84

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I didnt actually plug it into the connector, i did like u mentioned and used a wire to pos and neg

 

 

Ok so we know the pump works, and that there is constant power at the pump connector, so the only thing missing is ground,I'm an electrical engineer by trade and this is the best way to find a problem, It should be a Black wire. I'd pull the connector and make sure the - wire is well seated in the connector and corrosion free, use a meter and check continuity from that wire to the body, turn the meter to OHMs can't make the symbol on here, it should read 0.anything more then 0 then the ground is bad.

 

also does your fuel gauge read corectly?

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