Try replacing the spark plugs with a new set of NGKs, changing the fuel filter (if your's has one), and installing a new air filter. If the problem persists, consider replacing the igniter and coil, especially if you have 120,000 miles or 10 years on the vehicle. You may also want to use a strobe light and check the timing.

I've changed all but the coil

What year, model, and engine?

Did the engine overheat, causing the head gasket to blow? Remove all of the spark plugs and check the compression.

95 civic 1.5

The last Honda I worked on that had a lack of power was caused by a bad exhaust pipe that was plugged... just a thought!!

Good thought, Camaro00440--a bad catalytic converter is also a possibillity.