[4wd150]

hey everyone. moms 95 taurus just recently got a new fuel pump installed, then the gas guage was very inaccurate, it reads way less than what is actually left in the tank and will not go into the blue full part when filled at that pump. took back to shop 3 times and they tried different brands fuel pumps and it kept on the same thign with the inaccurate guage. also they replaced the float in the tank twice. anybody have any idea of why the guage is way off after having this work done? thanks