Fuel tank leaking

Hi,

There are a number of different reasons that this could happen but the main reason is a leaking fuel line or seal from on top of the tank. Unfortunately, the only way to know is to remove the tank and inspect it.

I included the procedure on how to remove the tank. You may not need to completely remove it, just gain enough access so you can see on top of the tank. You will want to do this with a close to empty tank or it will be heavy.

Let me know if you have questions.

Welcome to 2CarPros. It could be many things. Does it leak only when you fill it or with a full tank and rough roads or turns? Or does it leak only when the key is on?
For the first it could be a loose fill neck or a failed pump retainer ring that has let one of the modules lift enough to leak.
For the second it could be a bad pressure or return line fitting that has cracked.

To determine which an inspection camera that you can use to look at the parts that attach to the tank would be about the easiest way to see where the leak is. Then it would depend on what is leaking and where it is as to what the repair is. The fill neck being loose would be the easiest repair as you can get to that with the tank in the vehicle. If it is one of the modules the tank would need to be removed to remove and repair the problem.

REMOVAL PROCEDURE
Ensure that the fuel level in the tank is less than 1/4 full. If necessary, drain the fuel tank to at least this level. This can be done using the fuel pump and a line connected to the pump output.
First you will need to disconnect the negative battery cable.
Next you need to lift the vehicle up high enough to work under it. For the fuel tank you will want a lift as ramps or jack stands are not high enough to drop the tank fully.

Next you need to remove the rear section of the exhaust system from under the tank.

Now blow any dirt and crud off of the top of the tank and the lines. The EVAP canister also needs to be removed. Then you remove the filler neck, EVAP and other lines from the tank.
Next you remove the wiring connections from both sides.

Next you need to support the tank and remove the tank straps from the mounts. Do not disconnect one end and let the tank down that way, bending the straps can cause them to crack. One the straps are off you can gently lower the tank and remove it.
Then it can be repaired.