I have a 2004 Optima, with about 124k miles, that since November I have had nothing but mechanical issues. It started with Check Engine light. Took it to reputable auto sales dealer, whose mechanics replace the Master Air Flow sensor. The next day, the
car ran horribly, so I took it back and they replaced the MAF and put a throttle control sensor. SInce then, the throttle control has been replaced three times. They suggested replacing the timing belt, which they did, still showed check engine light. They
took it to a Kia dealership, who claimed nothing showed up on their computers. I had a local auto parts store put it on a computer and it kept showing a problem with the O2 sensor, but the repair place put it on a machine that says the O2 sensor was right
on. Now, if I am at a stop and try to quick accellerate onto another road, the car almost stalls out and then decides to go. This is a dangerous thing, if I am trying to get on the road where traffic is coming. Doesn't happen all of the time, but it does get
your attention. What do you think?