Isuzu Repair: 98 Izuzu Rodeo, gauge needle, fuel gauge

Question
I have about 130,000 miles on my truck, and for the past few months, my fuel gauge has been acting crazy, for instance I start it in the morning and immediately the gauge needle starts moving back and forth and the gas light starts blinking.  Also when this happens the fan comes on almost simutalinously, even though the car hasn't even warmed up.  So basically I can't tell how much fuel I have in the tank.

Answer
Fuel level sending unit is bad Mario. 200% positive. Look on ebay for your make year and model and they will have what you need for under fifty bucks. It takes about 3 hours to install and make sure you are very gentle with it!!!! Also make sure to seal the tank the CORRECT way or you will have hard starting and stalling problems in the future. Any other questions I am all ears!!!