I am having a huge issue with my 1996 chevy k1500 with the 5.7l Vortec. I seem to have a "face plant" right at 4000 rpms. So far I've replaced the entire distributor, fuel filter, spark plugs, cam position sensor, throttle positions sensor, I cleaned the mass air flow sensor and I've replaced the air filter. It seemed to me before the this face plant was misfire. But after I replaced everything to stop the overall misfire to where the engine runs smoothly up until 4 grand, the face plant must not be misfire. Im having a lot of issues with this. If I put the petal to the floor it will accelerate fine until it hits 4 grand. At that point the engine basically shuts down. The rpms will not pass 4 grand and if it does, it surges quicky past then falls right back down. The face plant only happens when I'm into the throttle at least halfway or so. If I'm just in park and I give it a small amount of throttle, it will pull redline and not face plant. It's only if I'm really mashing it that it will face plant. If anyone has any ideas or fixes, let me know. Thanks.