I drive a Dec 2004 Sonata S20 (Manual transmisssion 2.0 liter petrol/gasolineengine, done about 32100KM/20000miles). Of late it has developed a quirky habit: a jerky power delivery when between 1000 to 2000 RPM; it is not consistent, but happens often enough to worry. When it does occur, it is kind of like the engine is about to stall and suddenly surges ahead; I have observedthis happen at all gears 1-5except the reverse.Is it due to: (1) Fuel filter (2) Fuel pump (3) Unclean fuel injector (does not happen at higher RPM at all!) (4) Air filter (5) Exhaustor something else? I am very sure that the car is not equipped with a turbo.

I have not yet taken the car to the dealer aswanted to be educated by a diverse forum of experts before I do that.

Thanks,
Nagesh

 

You need to get an ODB II code reading to see if you have any fault codes. Otherwise you are shooting in the dark.

 

I still have not had time to go to the dealer. However, I did fill the petrol (gas) from a different petrol (gas) station and the incidence has reduced. In the meanwhile, I am curious if I can read the ODB II code myself: is it a USB or a serial connection to your laptop to download the data? Would you have any more information or pointersto how one could download this themselves if one were not able to visit the workshop?

 

Finally solved! There was no error on the hand-held scanner when we took the car out for a spin. The power delivery was jerky all right, at 1000-2000 RPM even after servicing (that involved spark plug cleaning). The spark plugs were replaced and the problem has now gone.

Thanks,
Nagesh

 

Very good. Hopefully it didn't cost too much.