I've got a 03 Ranger 3.0 V6. Whenever the RPM's get to between 3000-4000 the engine misses and cuts out for a brief second before continuing to accelerate. It keeps happening until I shift to the next gear and the RPM's drop. I've changed the plugs and wires several times. Put a new air filter, fuel filter and had the fuel system cleaned twice. Ford told me I needed new heads so I put new heads on and the check engine light i was getting is gone, but the engine keeps cutting out at high rpms. I think it was probably two unrelated problems. Has anyone else had a similar problem and if so what was it? Does anyone have any ideas? I think it is probably a sensor. Ive taken it to my families mechanic, pepboys twice, and ford. Thanks.