Not the fuel filter; the pickup screen in the tank. If it's a carbureted engine, that will indeed allow it to idle but not run well at higher speeds even as low as 20 mph. If it has fuel injection, a plugged screen will cause the engine to run best at highway speeds and it will typically stall when letting off the gas. The pump has to move the largest volume of fuel during coasting. When the screen is plugged or collapsed, that higher volume can't get through so pressure drops. When it drops low enough insufficient fuel will spray from the injectors, and the engine stalls.
Tuesday, February 8th, 2011 AT 1:31 AM