There are times when a co has had a bad run and three from the same source being bad is not unusual.

If you are getting the odor of gasoline that is important in itself to determine the cause.
Any vapors should be contained. You will need to trace all lines for any leaks and anything unusual since anybody could have done something incorrectly before you bought the vehicle.
The habit of continued filling after the pump shuts off at the gas pump causes problems when the charcoal from the vapor canister starts to float around the vapor control system (Evap System).

 

I only replaced one module (rear). The odor of gas was a result of returning fuel to a full tank. The problem is no matter which tank I'm drawing fuel from the return is going into the other tank.