Cant find 30 second fuel relay on 89 chevy silverodo 2500

Should be in the motor compartment fuse box.

It's in betweenthe inner fender and the fender itself. You have to take the front of the inner fender loose to find it. Your fuse or horn relay may be bad. relays are interchangable.

check conections if good replace sending unit

sorry to tell you this but there is no fuel pump reset button on the 1999 chevy silverado

Those are pressurized pump in the fuel tank. You should have a inspection access plate on top of the fuel tank(s). If there is more than one tank be sure the relays and the system to change over tanks is working properly. First thing starting it , in the morning , turn all out side noise off, turn key to on position just short of cranking the engine over ,and you should be able to hear the pump in the tank , making a low growling noise , if it is working propery , this will last about 30 seconds while the pump builds pressure.

Hi, if it's a diesel engine, they all have to sit for some seconds because of the glow plugs. Some diesel don't send power to the starter until the glow plugs run for the pre-determined amount of time. There are many things that could be causing this. Fuel filter, clogged injectors, fuel pump going bad or bad connection to fuel pump. Try checking out for this things..
Take care

You didn't mention fuel filter in your list. That would be the first thing to change.

Unplug the oil pressure sending unit. If pump stops then replace it.

Sounds like you have a power problem. If your not getting power from the battery the your injectors are not going to be pumping fuel. Check your battery

weak pump possible,wiring would ber all the time,relay could be relay its the cheapest part so id start there