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73-87 Chevy _ GMC Trucks => 73-87 Chevy & GMC Trucks => Topic started by: Lucky87 on June 05, 2011, 10:57:25 pm
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Ok so first I'll give the facts: 1987 GMC Sierra 305 TBI. Now the problem I'm having is I cannot get the truck to start. I drove it home from the shop and it died in front of my house and will not start back up. I know I'm getting spark because it started for a second when I poured gas into the TB but I don't seem to be getting gas. I tried listening for the fuel pump to prime by turning the key to run but I don't hear anything. I checked for power at the fuel pump relay and that was fine. I also dropped the tank and tested for power to the sending unit and I seem to be getting power there also but the fuel pump is still not turning on. Bought a new fuel pump but now I'm wondering if there is a way to test it on the truck without installing the tank because I do not want to drop the tank again. Also does the fuel sending unit have anything to do with the fuel pump and could it be the problem?
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You don't have to drop the tank to check for B+ at the pump. The pump will prime for 2 seconds when the key is turned on with 15 second intervals between key cycles. There is also a jumper at the fuel pump relay that you can bypass a fused jumper wire to B+ to prived constant B+ to the pump. If you have B+ to the pump but no pump, check the ground circuit. If OK replace pump
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Thanks for the reply I need all the help I can get. Right now I already have the tank off and the old fuel pump out but I want to make sure I fix the problem before reinstalling everything. If you don't mind, can you explain where exactly the jumper is at the fuel pump relay and how I go about bypassing the relay and also what exactly will that do? Pretty new to this electrical stuff so be patient with me. Thanks again.