1988 3.0 with 250K Increasing hesitation during the last month, In Drive. Mostly in the 40mph range, but stopped at lights, too.. Still gets me where I need to go but am worried it will just quit. (I work in a dangerous part of town) Seems to commence after a few blocks. Hoped it was just fuel filter, & changed it but the problem remains. Research suggests fuel pump or head gasket problem. How can I tell the difference? And what is outlook if I just ignore it for the time being. Head gasket is expensive repair and changing the fuel pump looks like a bear. Any thoughts? Prognosis?