How many volts should a lift pump be getting?

[HillbillyD-Luxx]

I have an earlier post about my lift pump, working on it now since it warned up a bit. Does anyone know how many volts the lift pump should be receiving? I drained my fuel filter bowl, then cycled my key. There was No fuel coming out of the pump, and it didn't kick on. I am getting a reading of 7.3 volts when the key is in the on position, but 12.3 when you crank the motor over. Should the lp always be getting 12v or is it a variable speed? Or an I getting a backfeed voltage of 7.3?

 

[07srt6]

Yes it should always have 12 volts, check the wiring

 

[crpower]

Pump could be going bad 3rd gens are known for it.


Sent from my iPhone using Tapatalk

 

[07srt6]

Pump could be going bad 3rd gens are known for it.


Sent from my iPhone using Tapatalk

I think there more reliable then the aftermarket pumps that use a brush motor.

 

[HeTheAethyr!]

....

 

[94 12valve]

if the voltage is right to the pump what pressure should be pump produce to the CP3?

 

[smalley]

When you first turn the key on, the pump runs for a set amount of time until you try to start it. If you don't try to start it, it will shut off and then cycle back on. I cant remember the length of time that all of this happens in. When you crank that truck, and when it is running, the pump will run of course. What year is the truck?

 

[HillbillyD-Luxx]

When you first turn the key on, the pump runs for a set amount of time until you try to start it. If you don't try to start it, it will shut off and then cycle back on. I cant remember the length of time that all of this happens in. When you crank that truck, and when it is running, the pump will run of course. What year is the truck?

2003. The pump will turn on when you turn the key on, and shuts off after about 30 seconds of run time if the truck isn't started. It still does this like it's supposed to, but when the lp cycle is over, i get 7 volts to the lp. not sure if it's supposed to be 0 volts? is the reading of 7 volts normal for after the pump has cycled?

 

[smalley]

When you are testing this, are you using the ground in the block or something else?

 

[HillbillyD-Luxx]

When you are testing this, are you using the ground in the block or something else?

The ground in the plug (it only has 2 pins)

 

[smalley]

That signal comes directly from the computer. There aren't any relays or fuses on it. If I remember right, I could never get mine to read anything that made sense either when I was having problems.