Originally Posted by
idrivejunk
That would be a small repair if you catch it soon, but it looks to be rusting through from the inside. Layers of steel meet in an odd shape in that area under the gas neck and as with typical rocker panel corrosion hotspots on all W bodies, there was just never enough primer or paint on the inner structure so they rust in wintery areas. Chances are you can jab a phillips head through that spot now, and that theres more on the next layer behind that. I patch rusty stuff for a living and think oh... probably six hours work would get that ready for primer and paint, figuring that theres another small rustout behind it. But since you're not planning to keep it, you'll probably want to consider a shadetree fix with spray paint rather than take it to a body shop.
Use a light and get a good look around inside the wheelwell. Take wheel off for a good inspection. Poke at stuff with a pick tool if you're brave and see bubbled coatings there. On Pontiacs at least, there was a re-design of the plastic splash shield for better salt protection in the gas fill area, see about that perhaps. It would be wise for you to also inspect your rear strut tower tops, in the trunk. And the rocker panels (where you jack it up and behind the rocker molding) because they are usually rusty if you find rust anywhere on it. Here, they don't rust much at all. If you find that the bubbly area is solid but just rust pitted, the rot may have started from a paint chip or scratch there on the exterior. That would not be a tough fix if the metal can be saved.
