How to wire electric water pump?

[Samckitt]

I had two thoughts on how to power an electric water pump. The motor is a 95 LT1.

Thought 1: Power a relay that would turn the pump on when the ignition is in the run position. Pump would continue to run if the engine was not running.

Thought 2: Power the relay from the PCM that energizes the fuel pump relay. Water pump only runs when the fuel pump is running. Engine stops / fuel pump stops / water pump stops.

Or other method?

[fiorano]

wire it to a dash switch and turn it on when you turn on the car, and leave it running during cool down if you want. or wire it to a thermo-switch so it turns on as soon as the car get to 150 degrees...

[GetMore]

I would wire it off the PCM and maybe install a manual switch.
I definitely wouldn't use a temp sender to turn it on, since no coolant will circulate until the coolant at the sender gets hot. If coolant isn't circulating then you don't have a good signal to the sender.

[megaladon6]

is it a single or multiple speed? if it's a single speed, wire it to the ECM with an emergency backup/afterrun switch. if it's multi-speed do the same just use a temp controller for the other speeds.

[Samckitt]

It is a single speed.

[megaladon6]

now if you wanna get really fancy, you can try and find a pulse-width-modulater and use that to control the pump. this way it uses less power and can regulate flow based on speed.