Hyundai Repair: 2003 Sonata, 2003 hyundai sonata, hyundai sonata

Question
Hi,

I have a 2003 Hyundai Sonata V6, automatic transmission with about 85,000 miles on it.  A couple times when I've been going down the interstate with the cruise control on, not touching anything, the car jerked a little bit.  It feels about the same as if I had tapped the clutch while not taking my foot off the gas (note this is an automatic... just trying to give an example).  Any idea what could cause that?

Thanks

Answer
I'm not sure I have a real good feel for exactly what's occurring, but it sounds like there's a transmission related problem or a momentary lack of engine power.

In fact, there's a technical service bulletin (TSB) for the momentary lack of engine power.  Hyundai calls it an "intermittent hesitation."  What I learned in my training classes is that the engine turns off momentarily while doing highway driving, causing an effect that feels similar to running over a pothole.  The solution to this is to reprogram the engine control module as outlined in TSB 04-36-015.  Any Hyundai dealer should be able to do this reprogramming for you.  Unfortunately, at 85,000 miles, you're outside the warranty period.

I'd recommend checking your transmission fluid first.  If okay, then have the reprogramming done.  If that still doesn't solve the issue, then I'd recommend reading the engine and transmission diagnostic trouble codes to see if there are any present that would provide a further explanation as to the cause of the problem.