Now, I have this in TWO threads (just to be sure).
I agree with redstangbob about checking the tank for old gas.
You can smell that distinctive varnish odor, before and after it burns. Better look under the trunk mat, pull the cover off, and look down your tank with a flashlight. Depending on how old, it could have left all kinds of varnish. And guess what... our new gasohol slowly breaks it up, sending pieces to your fuel pump.
You can stick a hose from your fuel pump into a gas can, just to err on the side of caution. This might be a good idea because it's time to change your rubber fuel line, anyway. - Dave