captain143

Good afternoon, XJ lovers!
I have recently acquired a 1992 XJ Laredo beauty. Automatic. 2 Wheel drive. In-line 6. Overall, she's in great shape and I love her.
I've noticed a noise coming from the rear of the vehicle I first noticed it when driving. It's not there on initial startup, but grows louder over time, during the drive.
I stopped the other day and opened the tailgate door while the truck was still running. The noise seemed to be coming from just below the cargo area, I guess where the fuel container is.
The best way I can describe the noise is like a "running" sound. Like a blower or motor. It gets so loud when driving that only loud music drowns it out.
Please forgive my ignorance. I'm new to this but am anxious to learn as much about this truck as I can. The only think I can think of that makes sense is possibly the fuel pump...?
I don't know if this sound is normal or not, but It seem way to loud to be commonplace.

Any advice or information would be super helpful!