98 honda civic coupe - Sometime but rarely the a/c compressor will kick on and blow cold air (at high speeds only). What could be the issue?

 

Could be a lot of things. Did it gradually get like this, or did it just suddenly go from working great to this current behavior? If you warm the car to operating temp, turn on the A/C full blast and hold idle at ~1500 RPM, does the condenser fan engage? Does the compressor clutch engage and stay engaged? What happens if you get a long extension bar or something and wiggle the compressor wires a little bit? Any change? If you don't have manifold gauges, one thing you can do is get under the car with a flashlight and mirror and carefully inspect the wiring on and leading to the compressor itself. Especially around the folded metal wire "protector" on the compressor where the main power wire goes under the metal. That thing is notorious for rubbing the red power wire leading from the connector plug to the compressor, especially if the connector/pigtail is not clipped into the frame properly. Inspect the other wires too. If you have feeler gauges, make sure the clutch plate is between .014-.026" away from the pulley.