I just changed it today. The sound is still there. Should I try changing the spade connectors that attach to the ballast? Because those were corroded also.

 

If you have new connectors then certainly change the old corroded ones to fresh new ones. This shouldn't make anything quieter though as you're only improving the voltage to the pump by using clean connections.

 

I replaced the ballast and the noise is still there at the same volume. Will be replacing the connectors next.

 

so should I try replacing the fuel pump assembly?

 

Disconnect the wires from the ballast resistor and connect them together. Start the motor and if you still hear the same sound with it disconnected, either your ballast resistor is no good and passing all 12 volts to the pump, or you have a noisy pump. Hope this helps.

 

It is starting to sound like that is the only step left to take.

 

I've never seen a ballast resistor short internally. Typically they crack and fail open, resulting in no voltage to the fuel pump and the engine dying once the key goes back to the run position after starting. Or someone replaced it with one of the wrong resistance and the fuel pump isn't getting enough juice.

The ballast resistor makes a great place to check if the fuel pump is getting current, btw. I measured mine recently while troubleshooting a no-start to check if the fuel pump was running. The voltage at the resistor drop to zero a few seconds after key-on and no voltage while cranking - which meant the computer wasn't seeing the cranking which led me to the CPS sensor. Once running, I had 13.5 volts on one wire, and 9.5 volts on the other (I think the resistance is somewhere around 1.2 ohms, so that makes it about 3 amps).

 

Is not the formula ohms gazinta volts = amps?

 

(4 volt drop across the resistor) / (1.2 ohms) = 3.3 amps

 

OIC.

 

I've replaced a few fuel pumps in the XJ over the last 23 years. Never replaced the Ballast. I installed one fuel pump that was terribly loud all the time. It lasted about 4 years. I Installed another fuel pump two years ago and it is quiet. The only thing I hear is the initial fuel line prime when turning the key to the on position.
Here's a tip: turn the key to on position, wait for the fuel prime, then turn the key to the start position. That technique will cut out the couple extra seconds on the front end of the engine cranking over.

 

I eneded up replacing the fuel pump. The noise is gone. Makes sense now because the pump that came out was the original from the factory in 1992!!

 

I'm guessing it was wearing out then. What once was made to tight tollerances had become a loose mess. A buzzing loose mess at that.