Well, i just replaced the fuel filter on my 1994 ford bronco, and now couple times i drive somewhere, the check engine light flashes, and the truck's rpms drop, sputters, almost dies, but keeps going, and when i take my foot off the gas, it still applies gas, up to 1500 Rpm, not alot, but even when i push on the brakes, it still accelerates, but not when i come to a full stop. Several months ago, a buddy and i took off the exhaust pipe and muffler, to make it retain a more throaty roar, but i'm wondering if that could be the cause for the engine problem. But i believe it to be another problem., the idle air flow valve, hasn't been changed in awhile, and i believe that maybe the cause for the malfunctions, originally i thought it was the fuel filter, but ever since i've changed it, it's been acting the same or worse. What do you think?