Several possibilities:
If you have an All Wheel Drive (AWD) model, it could be that the differential fluid is low or the differential gears or bearings are failing or one or both of the wheel bearings are failing.
If you own a two wheel drive (2WD) model (which do not have a differential) it would possibly mean that the wheel bearings are failing.
it could be anything from a bearing to the splash shield on the brake rotors.
A bad muffler on a 96 civic could cause loud exhaust noise. The muffler could cause hard starting if it is stopped up.
Most likely the compressor. It could also be the valve in the system too, when refrigerant gets low. What sort of noise is it???
A bad tire weight can cause a rubbing noise on full left lock on your Honda Civic 1997. A bubble on the tire can also cause this.
Worn brake drum pads and possibly your wheel bearing.
when i turn on the ac in my 2000 honda civic it makes a loud noise when the fan is working what could that be ?
A leaking manifold seal on the intake will cause a popping noise on the 1996 Honda Accord. This can heard most clearly on days when the weather is cold because the seals tend to shrink.
Cracked Fly Wheel
Check the CV Joints both inner and outer. Probally a boot has failed and the joint has loss all grease.
A bad starter might make a noise. The starter could also go bad with no noise or warning. However if the starter is making noise then there is a problem that could cause failure at any time
A bad compressor belt can cause a whistling noise while running the air conditioner. A bad engine can also cause this noise.
If the Honda Accord makes a groaning noise when reversing the can be caused by bad hub bearings. Hub bearings are what allow the car's wheels to spin, if gone bad they can cause wheels to come fully off the vehicle.