Alright, so the car is a 1997 Civic LX automatic with no modifications. The problem is sometimes during acceleration or cruising, the engine still stop accelerating or holding a speed regardless of whether or not I am on the acclerator pedal. This problem used to be intermittent, like it would happen once and then nothing for a few days or even weeks. But now, it is becoming more frequent.
I've recently replaced the valve cover gasket and distributor o-ring and replaced the spark plugs and inspected the distributor cap and plug wires during that time and everything looked good, no cracks, corrosion, etc. I've also recently replaced the thermostat, did a coolant flush, replaced the radiator (previous radiator had cracked), and oil change. This problem was occurring before I did all that.
I have heard suggestions that it could be the crank sensor (?) or maybe the automatic transmission fluid needs to be changed. But, I figured I'd get some opinions from people who have worked with these cars longer before I started throwing money at it...

 

What CEL codes are thrown?

Is there a reason that you did not replace the plug wires, cap, and rotor?

Have you replaced the fuel filter?

 

Does the car get stuck at a certain speed and shudder somewhat? Mine did that until I changed the transmission fluid.

 

Yeah, this sounds like it. I'm going to replace the fluid today and adjust the throttle cable as throttle response seems to be not smoothe; like, I can't come from a stop and ease into the gas, I basically have stomp on the gas.
Thanks for the advice! No CEL. No stored DTCs that might not trigger a CEL either. If the above things don't remedy the problem, I'll look more into the distributor and plug wires. Problem just seems too intermittent for it to be those things...

 

A friend of mine had a similar problem on his 97 DX, he would be driving and even though he had his foot on the accelerator the car would lose power and would start to slow down. After trying to replace every single thing, he finally replaced the o2 sensor and his problem was solved. Hope this helps...good luck.

 

Just changed the tranny fluid today, so we'll see what that does. If nothing, then I'll probably try the 02 sensor...

Did your friend use an aftermarket o2 or genuine Honda part?