1990 GMC Suburban fuel pump

My wiring info for your model year isn't great. Did you test at the fuel pump connector, at rear of vehicle? With engine cranking, the tan wire with white tracer is voltage for the pump motor. Black is usually ground, my info info didn't show ground wire. If good voltage and ground at the pump and no pump action, I suspect the pump. Did you check for fuel pressure with a gage?

[quote:b591c84353="internetmechanic"]My wiring info for your model year isn't great. Did you test at the fuel pump connector, at rear of vehicle? With engine cranking, the tan wire with white tracer is voltage for the pump motor. Black is usually ground, my info info didn't show ground wire. If good voltage and ground at the pump and no pump action, I suspect the pump. Did you check for fuel pressure with a gage?[/quote:b591c84353] * Yes I did check at Fuel pump connector.Wire Red got power strong light,Tan no power must be ground? Does that sound right to you? These wires are coming from power source to connector clip then to wires to fuel pump. I don't have a Pressure Gage,but when I checked the Fuel Filter there was some Pressure,so I don't think there any pressure now since the Fuel pump has 'NT came back on. Thanks for your time and help.

The tan wire with white tracer is voltage for the pump motor, the pink wire should be voltage for the sending unit, gas gage. Some of the national brand autostores used to loan out a fuel pressure gage, if you don't have one?

[quote:276c13b536="internetmechanic"]The tan wire with white tracer is voltage for the pump motor, the pink wire should be voltage for the sending unit, gas gage. Some of the national brand autostores used to loan out a fuel pressure gage, if you don't have one?[/quote:276c13b536] So then if the tan with white isn't getting power what would be the problem?

Possible problem with the relay or relay circuits. Check the ecm B fuse and circuit for voltage.