Same problem here with same engine. when the problem started a month ago I but in a new cat, both ox. sensors, all new plugs & wires, and new injectors just today. I dropped the fuel tank and cleaned out some rust w/ acid. I inspected and cleaned the fuel pump at the same time (its one year old). Nothing looke melted. When engine warms up, it cannot wind out more than 2100 RPM, this decreases until the limit is about 1,200 RPM and max speed at this point is about 15 MPH. Runs fine when cold and wrming up, and idles fine too.
