My 1999 Kia Sehia Has Trouble Accelerating From Dead Stop.after 10 Mph It Goes

The tps, throttle position sensor may not be working. This would lead to rough idle, and some loss of power, but it could also be a misfire in one of the cylinders. Check plugs, leads, etc. Ask yourself does the car need a service, when was it last done? It would be best if you could get a read out of any fault codes that may be stored in the ecu first, find a garage that will use a code reader to do this, cheaply mind, or get one for yourself. There are many other issues that can be involved, but check the cheapest first, plugs leads etc. Tps sensor is a best bet for rough idle on tick over, and during a journey.