2003 Hyundai Sonata

Engine Performance problem
2003 Hyundai Sonata 4 cyl Front Wheel Drive Automatic 37000 miles

I have a 2003 hyndai sonata with 37000 miles. Occasionally the car will stumble while I am excellarating and the check engine light will come on and go out quickly. My local mechanic did not see any code from the computer. He says that it maybe the catalytic converter. The car does run sluggish sometimes
October 27, 2010.

Lack of acceleration, chugging, hesitating, jerking, bogging, misfiring etc. Could be caused by one of the following below

Oxygen sensor.
Catalytic converter.
Fuel injectors dirty/sticking.
Mass airflow sensor/Airflow meter.
Throttle position sensor.
Crankshaft position sensor
Knock sensor
Manifold absolute pressure sensor.
EGR Valve
Fuel pressure regulator leaking or defective fuel pump.
False air leakage.
Fuel contamination.
Foul/defective spark plugs.
Open spark plug wires.
Ignition coil/Coil packs defective.
Incorrect ignition timing.
Cap and rotor.

Note: If it doesn't apply disregard it

Oct 27, 2010.