2002 Kia Rio

Engine Performance problem
2002 Kia Rio Manual 69500 miles

i have a 2002 kia rio which keeps misfiring. When the engine is turned on the car starts as normal although the revs seem alittle low (below the no1). When I drive the car it misfires sometimes more than others. Its mostly when its in low gears such as 1 and 2, and sometimes when you change gear the revs needle drops fast and the check light flicks on then goes off after the gear change. Its had a new egnition sensor fitted as this was what the machine picked up was the problem but this has made no difference. Ive took the car to 2 garages who still cant find the problem. Please help
January 27, 2009.

Remove and replace the fuel filter. Add a good fuel cleaner to the tank to clean pipes and injectors !

Dave H
Feb 19, 2009.