1993 Mercury Villager rev limiter

I have a villager that at 2800 to 3000 rpms starts to buck and kick like the rev limiter is set there,once I ease off the gas it returns to normal until I get close to 3000 rpms this happens at all speeds I have never been able to pass 3000rpms even in park. I changed plugs,wires,dis cap rotor and cracked hoses still no change can you help?