TBI Fuel Pump Wiring

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MtBraun

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I am converting a 78 GMC K15 with gen 1 sbc/th350 to TBI from a 1991 Chevy 1500 donor truck. I upgraded the fuel system (tank/pump/sending unit) with new aftermarket 1987 V10 parts. The pigtail plug on the new fuel pump has two wires, grey and purple. The TBI harness has a grey wire from the fuel pump relay that should go to the pump. Since I had to cut the fuel pump relay harness before the tank plug on the donor truck, I just need to double check that grey to grey is correct here? And that the purple wire is for the tank level to gauge. Is that correct?

Thank you.
 

1987 GMC Jimmy

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I am converting a 78 GMC K15 with gen 1 sbc/th350 to TBI from a 1991 Chevy 1500 donor truck. I upgraded the fuel system (tank/pump/sending unit) with new aftermarket 1987 V10 parts. The pigtail plug on the new fuel pump has two wires, grey and purple. The TBI harness has a grey wire from the fuel pump relay that should go to the pump. Since I had to cut the fuel pump relay harness before the tank plug on the donor truck, I just need to double check that grey to grey is correct here? And that the purple wire is for the tank level to gauge. Is that correct?

Thank you.

When I replaced my fuel pump, I don't remember the wiring on it corresponding to my factory wiring colors. If I'm not mistaken tan/white should be the power going to the pump, and pink should be the signal wire for the gauge.
 

bucket

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The wires to the pump itself in the tank, or the wires that plug into the sending unit?
 

MtBraun

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The wires to the pump itself in the tank, or the wires that plug into the sending unit?

The sending unit plug. I verified in a subsequent search that the gauge level is purple and power to the pump is grey.
 

1987 GMC Jimmy

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Ahh, I thought you meant the wires going there and not the wires on the sender themselves. Glad you got it straightened out, though.
 

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