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I have a 2003 Hyundai Accent and when I had the oil changed today, it was recommended that I get a transmission fluid flush soon because the fluid is dirty, although it doesn't have a burnt smell (yet). I know I'm overdue for a change since I'm at 150,000 km and I've never had it done yet. Is a flush the safest way to go based on the mileage though? I'm worried any build-up that comes lose could cause damage in the future. But would just replacing the fluid (no actual flush) be sufficient enough? Please help! Thanks.

I have a 2003 Accent that I haven't had any major problems with until this fall. The "check engine" light came on, brought it to a mechanic and one of the oxygen sensors and MAP sensor had to be replaced. A week later it came on again and the other oxygen sensor was replaced. A week later it came on AGAIN! I brought it to a different mechanic who told me the problem was something else because both oxygen sensors and MAP sensor wouldn't all go off at pretty much the same time. He determined a new computer was required so that was replaced. Guess what happened the following week? Yeah, so brought it back to the second mechanic, he brought it to the Hyundai dealership thinking the computer (which was previously used) had to be reset. That was last week, and it just turned on again today. I commute a fair distance and it seems to come on after 400 km of highway driving. Does anyone know what else it could be? I read that it could even possibly come down to faulty signals from the battery or alternator? During this whole time there hasn't actually been an issue with performance; it runs very well. I'm just sick of seeing the check engine light all the time. Any advice would be really appreciated!