2003 Sebring Intermittent Loss of Power

I have a 2003 4 cylinder Sebring Sedan that is driving me crazy. Intermittently while driving at various speeds the car will loss horsepower for a few seconds, run rough and then return to normal.It never completely stalls.Bewteen these occurrences the car runs flawlessly Sometimes the CEL comes on before the problem occurs, stays on for awhile after and clears. Had the Car to a mechanic on 2 different occasions. Based on diagnostic codes an O2 sensor and a crankshaft sensor were replaced. The problem is still not fixed. Could the problem be intermittent fuel pump? Could the sensor failure codes be a side effect of a fuel system problem. Thanks in advance.

what engine?

will determine a response.

It has the 2.4L V4 in it.

Get a scan of the powertrain control module, free at many larger chain auto parts stores, for diagnostic trouble codes. Post the exact results here.

Does this happen only when the engine is under a fairly heavy load? That can result from a fuel starvation problem, like a clogged fuel filter or failing fuel pump.