Hi, My name is XXXXX XXXXX X can assist you.
What you have described is a problem with the sending unit o ring that goes directly under the sending unit and seals the fuel tank and allows the sending unit to be removed for service. The other possibility could be the vapor vent valve seal also located on the top of the fuel tank. What will have to be done is to have the vehicle de fueled then the fuel tank will have to be removed for inspection. Not a simple task. One simple task that you coud preform prior to the tank removal would be to look at the fill neck hose to see if you see any fuel leaking at the clamp area. If so tighten it up, refuel vehicle and you may have saved yourself bunch of money.
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