my son just recently bought a 2000 Blazer. A week later the gauge would read full and then drop back to E, the low fuel light would come on and then back to full. He filled it up and it took 6 gal. Now the gauge is going down slowly but it stopped at 3/4 and he has gone 180 mi. It has a
20 gal. tank. My quest. is what are the possibilities and is it an expensive fix. Thanks.