Four problems related to engine have been reported for the 2003 Hyundai Sonata. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2003 Hyundai Sonata based on all problems reported for the 2003 Sonata.
Engine misfiring.
While traveling on the highway and without prior warning, especially when going up hills, the vehicle lost power, it happened at least 5 times. The dealer stated there was no repair and to make sure the vehicle always had a tank of gas before going up a hill.
Engine check light comes on when driving vehicle.
The engine does reliably accelerate when the accelerator pedal is pressed. Sometimes there is up to a 3 second delay before the engine responds to commands from the accelerator pedal. At times the engine also accelerates very sluggishly compared to other 2003 4-cylinder. Hyundai Sonatas that have been tested. Hyundai hasn't corrected this problem despite many attempts.