Intermittent rough idle in 95 accord LX
When cold in the am car starts fine, after about ten or twenty minutes it develops an intermittent rough idle that gets worse as the day progresses only to get better the next morning when cold. Exhaust note changes to a hollow sound like post ignition and there is some exhaust blow out at the first gasket when the idle is rough. When running fine no exhaust leak. Runs fine at highway speeds but idle will drop to almost nothing at the end of exit ramps, sometimes stalls as rpms come down at stops. Car will shudder when starting on a hill or starting fast (manual trans) unless I rev it up more than normal. Exhaust smells rich but no rotten egg smell. New plugs, wires, cap, ignition control module, rotor, coil, throttle position sensor, cleaned IAC valve. Running out of parts and in need of some diagnostic advise.