I sometimes have no clutch pressure.

Hello, You likely have a bad clutch master cylinder. When you press the clutch, and find no pressure, do you find that pressing a couple more times allows the clutch to move? As far as hesitation, you may be having one of many issues, but without more symptoms it is difficult to narrow it down. You may have issues with the idle air control valve (IACV), exhaust gas recirculation system (EGR), a weak ignition coil, spark plugs, spark plug wires, distributor cap, or distributor rotor, fuel pressure issues, or even a vacuum leak. Unless you have other symptoms pointing you towards a particular system, it may be best to have it diagnosed by a professional.