2002 3.0 ranger w/ manual trans. Engine just seems to die when trying to accelerate past 4000 rpm, but only after it has warmed up. So far I've cleaned Mass Air Flow sensor and replaced air filter, fuel filter, PCV valve and tube, spark plugs and wires, coil pack, and battery. Tested fuel pressure, was at 65psi with truck running. Injectors all have same resistance. All cylinders have 180 psi compression. Any thoughts what this could be? Not that it cant drive me around just fine under 4k, but would like to get to the root of the problem. Thank you.